Add --disable-newlib-fno-builtin to allow compilation without -fno-builtin for smaller and faster code.newlib-snapshot-20180831

102 files changed, 1436 insertions, 228 deletions

diff --git a/newlib/acinclude.m4 b/newlib/acinclude.m4
index 8c2cdc3b8..19dfe0864 100644
--- a/newlib/acinclude.m4
+++ b/newlib/acinclude.m4
@@ -92,6 +92,16 @@ AC_ARG_ENABLE(newlib-supplied-syscalls,
 
 AM_CONDITIONAL(MAY_SUPPLY_SYSCALLS, test x[$]{newlib_may_supply_syscalls} = xyes)
 
+dnl Support --disable-newlib-fno-builtin
+AC_ARG_ENABLE(newlib-fno-builtin,
+[  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions],
+[case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   AC_MSG_ERROR(bad value ${enableval} for newlib-fno-builtin option) ;;
+ esac], [newlib_fno_builtin=])dnl
+
+
 dnl We may get other options which we don't document:
 dnl --with-target-subdir, --with-multisrctop, --with-multisubdir
 
@@ -202,8 +212,6 @@ fi
 
 . [$]{newlib_basedir}/configure.host
 
-newlib_cflags="[$]{newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 AC_SUBST(NEWLIB_CFLAGS)
 
diff --git a/newlib/configure b/newlib/configure
index d88180863..192a0b37a 100755
--- a/newlib/configure
+++ b/newlib/configure
@@ -813,6 +813,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 enable_shared
@@ -1487,6 +1488,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -3170,6 +3172,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -4016,8 +4030,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
@@ -11828,7 +11840,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11831 "configure"
+#line 11843 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11934,7 +11946,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11937 "configure"
+#line 11949 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/newlib/configure.host b/newlib/configure.host
index bfa51669d..7e9336a0a 100644
--- a/newlib/configure.host
+++ b/newlib/configure.host
@@ -28,6 +28,7 @@
 #   newlib_io_long_long --enable-newlib-io-long-long ("yes", "no", "")
 #   newlib_io_long_double --enable-newlib-io-long-double ("yes", "no", "")
 #   newlib_global_stdio_streams --enable-global-stdio-streams ("yes", "no, "")
+#   newlib_fno_builtin  --disable-newlib-fno-builtin ("yes", "no, "")
 
 # It sets the following shell variables:
 #   newlib_cflags	Special CFLAGS to use when building
@@ -91,6 +92,19 @@ case "${target_optspace}:${host}" in
     ;;
 esac
 
+case "${newlib_fno_builtin}:${host}" in
+  yes:*)
+    newlib_cflags="${newlib_cflags} -fno-builtin"
+    ;;
+  no:*)
+    newlib_cflags="${newlib_cflags}"
+    ;;
+  *:*)
+    # For now, all targets default to using -fno-builtin until tested without
+    newlib_cflags="${newlib_cflags} -fno-builtin"
+    ;;
+esac
+
 # Get the source directories to use for the CPU type.
 # machine_dir should supply CPU dependent routines, such as setjmp.
 # newlib_cflags is passed to gcc when compiling.
diff --git a/newlib/libc/configure b/newlib/libc/configure
index 448cf4dc5..add8f679c 100755
--- a/newlib/libc/configure
+++ b/newlib/libc/configure
@@ -808,6 +808,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 enable_shared
@@ -1460,6 +1461,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2930,6 +2932,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3776,8 +3790,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
@@ -11555,7 +11567,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11558 "configure"
+#line 11570 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11661,7 +11673,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11664 "configure"
+#line 11676 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/newlib/libc/machine/a29k/configure b/newlib/libc/machine/a29k/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/a29k/configure
+++ b/newlib/libc/machine/a29k/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/aarch64/configure b/newlib/libc/machine/aarch64/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/aarch64/configure
+++ b/newlib/libc/machine/aarch64/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/arc/configure b/newlib/libc/machine/arc/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/arc/configure
+++ b/newlib/libc/machine/arc/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/arm/configure b/newlib/libc/machine/arm/configure
index f20d0fd75..4b9ac6739 100755
--- a/newlib/libc/machine/arm/configure
+++ b/newlib/libc/machine/arm/configure
@@ -690,6 +690,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1326,6 +1327,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2490,6 +2492,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3336,8 +3350,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/bfin/configure b/newlib/libc/machine/bfin/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/bfin/configure
+++ b/newlib/libc/machine/bfin/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/configure b/newlib/libc/machine/configure
index 66afa17b0..be295f6fd 100755
--- a/newlib/libc/machine/configure
+++ b/newlib/libc/machine/configure
@@ -764,6 +764,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 enable_shared
@@ -1467,6 +1468,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2874,6 +2876,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3720,8 +3734,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
@@ -11490,7 +11502,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11493 "configure"
+#line 11505 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11596,7 +11608,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11599 "configure"
+#line 11611 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/newlib/libc/machine/cr16/configure b/newlib/libc/machine/cr16/configure
index 397abd875..6a6ad6044 100644
--- a/newlib/libc/machine/cr16/configure
+++ b/newlib/libc/machine/cr16/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/cris/configure b/newlib/libc/machine/cris/configure
index 785d06560..017a4d5e7 100755
--- a/newlib/libc/machine/cris/configure
+++ b/newlib/libc/machine/cris/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/crx/configure b/newlib/libc/machine/crx/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/crx/configure
+++ b/newlib/libc/machine/crx/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/d10v/configure b/newlib/libc/machine/d10v/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/d10v/configure
+++ b/newlib/libc/machine/d10v/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/d30v/configure b/newlib/libc/machine/d30v/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/d30v/configure
+++ b/newlib/libc/machine/d30v/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/epiphany/configure b/newlib/libc/machine/epiphany/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/epiphany/configure
+++ b/newlib/libc/machine/epiphany/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/fr30/configure b/newlib/libc/machine/fr30/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/fr30/configure
+++ b/newlib/libc/machine/fr30/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/frv/configure b/newlib/libc/machine/frv/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/frv/configure
+++ b/newlib/libc/machine/frv/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/ft32/configure b/newlib/libc/machine/ft32/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/ft32/configure
+++ b/newlib/libc/machine/ft32/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/h8300/configure b/newlib/libc/machine/h8300/configure
index e482434f6..d19497d9d 100755
--- a/newlib/libc/machine/h8300/configure
+++ b/newlib/libc/machine/h8300/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/h8500/configure b/newlib/libc/machine/h8500/configure
index cf6ad3828..e475ddd1f 100755
--- a/newlib/libc/machine/h8500/configure
+++ b/newlib/libc/machine/h8500/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/hppa/configure b/newlib/libc/machine/hppa/configure
index c7bac1f53..2b8a77c57 100755
--- a/newlib/libc/machine/hppa/configure
+++ b/newlib/libc/machine/hppa/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/i386/configure b/newlib/libc/machine/i386/configure
index 5341dfd85..76c10c78f 100755
--- a/newlib/libc/machine/i386/configure
+++ b/newlib/libc/machine/i386/configure
@@ -762,6 +762,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 enable_shared
@@ -1410,6 +1411,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2817,6 +2819,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3663,8 +3677,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
@@ -11433,7 +11445,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11436 "configure"
+#line 11448 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11539,7 +11551,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11542 "configure"
+#line 11554 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/newlib/libc/machine/i960/configure b/newlib/libc/machine/i960/configure
index c2ef65856..a2e46c224 100755
--- a/newlib/libc/machine/i960/configure
+++ b/newlib/libc/machine/i960/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/iq2000/configure b/newlib/libc/machine/iq2000/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/iq2000/configure
+++ b/newlib/libc/machine/iq2000/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/lm32/configure b/newlib/libc/machine/lm32/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/lm32/configure
+++ b/newlib/libc/machine/lm32/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/m32c/configure b/newlib/libc/machine/m32c/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/m32c/configure
+++ b/newlib/libc/machine/m32c/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/m32r/configure b/newlib/libc/machine/m32r/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/m32r/configure
+++ b/newlib/libc/machine/m32r/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/m68hc11/configure b/newlib/libc/machine/m68hc11/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/m68hc11/configure
+++ b/newlib/libc/machine/m68hc11/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/m68k/configure b/newlib/libc/machine/m68k/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/m68k/configure
+++ b/newlib/libc/machine/m68k/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/m88k/configure b/newlib/libc/machine/m88k/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/m88k/configure
+++ b/newlib/libc/machine/m88k/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/mep/configure b/newlib/libc/machine/mep/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/mep/configure
+++ b/newlib/libc/machine/mep/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/microblaze/configure b/newlib/libc/machine/microblaze/configure
index 90e6e690c..7ac546442 100644
--- a/newlib/libc/machine/microblaze/configure
+++ b/newlib/libc/machine/microblaze/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/mips/configure b/newlib/libc/machine/mips/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/mips/configure
+++ b/newlib/libc/machine/mips/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/mn10200/configure b/newlib/libc/machine/mn10200/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/mn10200/configure
+++ b/newlib/libc/machine/mn10200/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/mn10300/configure b/newlib/libc/machine/mn10300/configure
index c7bac1f53..2b8a77c57 100755
--- a/newlib/libc/machine/mn10300/configure
+++ b/newlib/libc/machine/mn10300/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/moxie/configure b/newlib/libc/machine/moxie/configure
index 397abd875..6a6ad6044 100644
--- a/newlib/libc/machine/moxie/configure
+++ b/newlib/libc/machine/moxie/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/msp430/configure b/newlib/libc/machine/msp430/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/msp430/configure
+++ b/newlib/libc/machine/msp430/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/mt/configure b/newlib/libc/machine/mt/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/mt/configure
+++ b/newlib/libc/machine/mt/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/nds32/configure b/newlib/libc/machine/nds32/configure
index eb50c630a..fb3b7a9ea 100755
--- a/newlib/libc/machine/nds32/configure
+++ b/newlib/libc/machine/nds32/configure
@@ -698,6 +698,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1339,6 +1340,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2510,6 +2512,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3356,8 +3370,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/necv70/configure b/newlib/libc/machine/necv70/configure
index e40c631de..a45a4592f 100755
--- a/newlib/libc/machine/necv70/configure
+++ b/newlib/libc/machine/necv70/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/nios2/configure b/newlib/libc/machine/nios2/configure
index 17110aa0b..762b15336 100755
--- a/newlib/libc/machine/nios2/configure
+++ b/newlib/libc/machine/nios2/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/nvptx/configure b/newlib/libc/machine/nvptx/configure
index 397abd875..6a6ad6044 100644
--- a/newlib/libc/machine/nvptx/configure
+++ b/newlib/libc/machine/nvptx/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/or1k/configure b/newlib/libc/machine/or1k/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/or1k/configure
+++ b/newlib/libc/machine/or1k/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/powerpc/configure b/newlib/libc/machine/powerpc/configure
index 18f4fdc54..1e98a3107 100755
--- a/newlib/libc/machine/powerpc/configure
+++ b/newlib/libc/machine/powerpc/configure
@@ -690,6 +690,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1326,6 +1327,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2490,6 +2492,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3336,8 +3350,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/riscv/configure b/newlib/libc/machine/riscv/configure
index 88d962ff6..0b9d601de 100755
--- a/newlib/libc/machine/riscv/configure
+++ b/newlib/libc/machine/riscv/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/rl78/configure b/newlib/libc/machine/rl78/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/rl78/configure
+++ b/newlib/libc/machine/rl78/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/rx/configure b/newlib/libc/machine/rx/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/rx/configure
+++ b/newlib/libc/machine/rx/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/sh/configure b/newlib/libc/machine/sh/configure
index 0f4602ff8..fccf05913 100755
--- a/newlib/libc/machine/sh/configure
+++ b/newlib/libc/machine/sh/configure
@@ -702,6 +702,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1344,6 +1345,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2555,6 +2557,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3401,8 +3415,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/sparc/configure b/newlib/libc/machine/sparc/configure
index 038f6359d..b36fb2643 100755
--- a/newlib/libc/machine/sparc/configure
+++ b/newlib/libc/machine/sparc/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/spu/configure b/newlib/libc/machine/spu/configure
index 1115fb285..86a29dabb 100644
--- a/newlib/libc/machine/spu/configure
+++ b/newlib/libc/machine/spu/configure
@@ -691,6 +691,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1327,6 +1328,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2491,6 +2493,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3337,8 +3351,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/tic4x/configure b/newlib/libc/machine/tic4x/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/tic4x/configure
+++ b/newlib/libc/machine/tic4x/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/tic6x/configure b/newlib/libc/machine/tic6x/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/tic6x/configure
+++ b/newlib/libc/machine/tic6x/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/tic80/configure b/newlib/libc/machine/tic80/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/tic80/configure
+++ b/newlib/libc/machine/tic80/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/v850/configure b/newlib/libc/machine/v850/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/v850/configure
+++ b/newlib/libc/machine/v850/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/visium/configure b/newlib/libc/machine/visium/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/visium/configure
+++ b/newlib/libc/machine/visium/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/w65/configure b/newlib/libc/machine/w65/configure
index cf6ad3828..e475ddd1f 100755
--- a/newlib/libc/machine/w65/configure
+++ b/newlib/libc/machine/w65/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/x86_64/configure b/newlib/libc/machine/x86_64/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/x86_64/configure
+++ b/newlib/libc/machine/x86_64/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/xc16x/configure b/newlib/libc/machine/xc16x/configure
index 4a27937f6..083cd071c 100644
--- a/newlib/libc/machine/xc16x/configure
+++ b/newlib/libc/machine/xc16x/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/xscale/configure b/newlib/libc/machine/xscale/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libc/machine/xscale/configure
+++ b/newlib/libc/machine/xscale/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/xstormy16/configure b/newlib/libc/machine/xstormy16/configure
index 4a27937f6..083cd071c 100755
--- a/newlib/libc/machine/xstormy16/configure
+++ b/newlib/libc/machine/xstormy16/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/machine/z8k/configure b/newlib/libc/machine/z8k/configure
index 62d7f9b7e..5291def96 100755
--- a/newlib/libc/machine/z8k/configure
+++ b/newlib/libc/machine/z8k/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/a29khif/configure b/newlib/libc/sys/a29khif/configure
index 05366c4d0..b8f9ce21e 100755
--- a/newlib/libc/sys/a29khif/configure
+++ b/newlib/libc/sys/a29khif/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/arm/configure b/newlib/libc/sys/arm/configure
index cc2f7e15a..5a500236d 100755
--- a/newlib/libc/sys/arm/configure
+++ b/newlib/libc/sys/arm/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/configure b/newlib/libc/sys/configure
index 9780edacd..209e79dbd 100755
--- a/newlib/libc/sys/configure
+++ b/newlib/libc/sys/configure
@@ -765,6 +765,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 enable_shared
@@ -1439,6 +1440,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2846,6 +2848,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3692,8 +3706,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
@@ -11462,7 +11474,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11465 "configure"
+#line 11477 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11568,7 +11580,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11571 "configure"
+#line 11583 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/newlib/libc/sys/d10v/configure b/newlib/libc/sys/d10v/configure
index c9a30f25a..88091acf2 100755
--- a/newlib/libc/sys/d10v/configure
+++ b/newlib/libc/sys/d10v/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/decstation/configure b/newlib/libc/sys/decstation/configure
index 3e3a9a23d..0e6ea6bb9 100755
--- a/newlib/libc/sys/decstation/configure
+++ b/newlib/libc/sys/decstation/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/epiphany/configure b/newlib/libc/sys/epiphany/configure
index 9f236baaf..fbd964946 100755
--- a/newlib/libc/sys/epiphany/configure
+++ b/newlib/libc/sys/epiphany/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/h8300hms/configure b/newlib/libc/sys/h8300hms/configure
index 3f2369ea3..648527413 100755
--- a/newlib/libc/sys/h8300hms/configure
+++ b/newlib/libc/sys/h8300hms/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/h8500hms/configure b/newlib/libc/sys/h8500hms/configure
index 23d46c3d7..29755c072 100755
--- a/newlib/libc/sys/h8500hms/configure
+++ b/newlib/libc/sys/h8500hms/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/linux/configure b/newlib/libc/sys/linux/configure
index b287fc419..0a0a172a8 100755
--- a/newlib/libc/sys/linux/configure
+++ b/newlib/libc/sys/linux/configure
@@ -765,6 +765,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 enable_shared
@@ -1414,6 +1415,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2821,6 +2823,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3667,8 +3681,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
@@ -11479,7 +11491,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11482 "configure"
+#line 11494 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11585,7 +11597,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11588 "configure"
+#line 11600 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/newlib/libc/sys/linux/linuxthreads/configure b/newlib/libc/sys/linux/linuxthreads/configure
index 64da3737c..14123ba53 100755
--- a/newlib/libc/sys/linux/linuxthreads/configure
+++ b/newlib/libc/sys/linux/linuxthreads/configure
@@ -764,6 +764,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 enable_shared
@@ -1412,6 +1413,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2819,6 +2821,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3665,8 +3679,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
@@ -11477,7 +11489,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11480 "configure"
+#line 11492 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11583,7 +11595,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11586 "configure"
+#line 11598 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/newlib/libc/sys/linux/linuxthreads/machine/configure b/newlib/libc/sys/linux/linuxthreads/machine/configure
index 17f94299b..903600f59 100755
--- a/newlib/libc/sys/linux/linuxthreads/machine/configure
+++ b/newlib/libc/sys/linux/linuxthreads/machine/configure
@@ -764,6 +764,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 enable_shared
@@ -1412,6 +1413,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2819,6 +2821,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3665,8 +3679,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
@@ -11435,7 +11447,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11438 "configure"
+#line 11450 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11541,7 +11553,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11544 "configure"
+#line 11556 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/newlib/libc/sys/linux/linuxthreads/machine/i386/configure b/newlib/libc/sys/linux/linuxthreads/machine/i386/configure
index 2ebc57144..e7d2f59dd 100755
--- a/newlib/libc/sys/linux/linuxthreads/machine/i386/configure
+++ b/newlib/libc/sys/linux/linuxthreads/machine/i386/configure
@@ -760,6 +760,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 enable_shared
@@ -1408,6 +1409,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2815,6 +2817,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3661,8 +3675,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
@@ -11473,7 +11485,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11476 "configure"
+#line 11488 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11579,7 +11591,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11582 "configure"
+#line 11594 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/newlib/libc/sys/linux/machine/configure b/newlib/libc/sys/linux/machine/configure
index 2dbb8e747..1be5b7f74 100755
--- a/newlib/libc/sys/linux/machine/configure
+++ b/newlib/libc/sys/linux/machine/configure
@@ -765,6 +765,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 enable_shared
@@ -1413,6 +1414,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2820,6 +2822,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3666,8 +3680,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
@@ -11436,7 +11448,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11439 "configure"
+#line 11451 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11542,7 +11554,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11545 "configure"
+#line 11557 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/newlib/libc/sys/m88kbug/configure b/newlib/libc/sys/m88kbug/configure
index a5968e4a5..0d637ac33 100755
--- a/newlib/libc/sys/m88kbug/configure
+++ b/newlib/libc/sys/m88kbug/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/mmixware/configure b/newlib/libc/sys/mmixware/configure
index 258903323..719158d1b 100755
--- a/newlib/libc/sys/mmixware/configure
+++ b/newlib/libc/sys/mmixware/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/netware/configure b/newlib/libc/sys/netware/configure
index 1ef0c8041..270e5783c 100755
--- a/newlib/libc/sys/netware/configure
+++ b/newlib/libc/sys/netware/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/or1k/configure b/newlib/libc/sys/or1k/configure
index a0aced9e1..3b666e93e 100755
--- a/newlib/libc/sys/or1k/configure
+++ b/newlib/libc/sys/or1k/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/phoenix/configure b/newlib/libc/sys/phoenix/configure
index 34a2766ca..0cff3e936 100644
--- a/newlib/libc/sys/phoenix/configure
+++ b/newlib/libc/sys/phoenix/configure
@@ -692,6 +692,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1328,6 +1329,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2492,6 +2494,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3338,8 +3352,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/rdos/configure b/newlib/libc/sys/rdos/configure
index 0fd364337..46913b413 100755
--- a/newlib/libc/sys/rdos/configure
+++ b/newlib/libc/sys/rdos/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/rtems/configure b/newlib/libc/sys/rtems/configure
index 1729ae1f3..c44d04332 100755
--- a/newlib/libc/sys/rtems/configure
+++ b/newlib/libc/sys/rtems/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/sh/configure b/newlib/libc/sys/sh/configure
index c9a30f25a..88091acf2 100755
--- a/newlib/libc/sys/sh/configure
+++ b/newlib/libc/sys/sh/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/sparc64/configure b/newlib/libc/sys/sparc64/configure
index b4bb54a0c..b77f8695e 100755
--- a/newlib/libc/sys/sparc64/configure
+++ b/newlib/libc/sys/sparc64/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/sun4/configure b/newlib/libc/sys/sun4/configure
index 50356cc73..daf2c663d 100755
--- a/newlib/libc/sys/sun4/configure
+++ b/newlib/libc/sys/sun4/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/sysmec/configure b/newlib/libc/sys/sysmec/configure
index 3f2369ea3..648527413 100755
--- a/newlib/libc/sys/sysmec/configure
+++ b/newlib/libc/sys/sysmec/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/sysnec810/configure b/newlib/libc/sys/sysnec810/configure
index e6bbc3a6c..2dd56346b 100755
--- a/newlib/libc/sys/sysnec810/configure
+++ b/newlib/libc/sys/sysnec810/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/sysnecv850/configure b/newlib/libc/sys/sysnecv850/configure
index 3f2369ea3..648527413 100755
--- a/newlib/libc/sys/sysnecv850/configure
+++ b/newlib/libc/sys/sysnecv850/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/sysvi386/configure b/newlib/libc/sys/sysvi386/configure
index 51cfa560d..010fde4f6 100755
--- a/newlib/libc/sys/sysvi386/configure
+++ b/newlib/libc/sys/sysvi386/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/sysvnecv70/configure b/newlib/libc/sys/sysvnecv70/configure
index 11b18a5d7..c6b12fbed 100755
--- a/newlib/libc/sys/sysvnecv70/configure
+++ b/newlib/libc/sys/sysvnecv70/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/tic80/configure b/newlib/libc/sys/tic80/configure
index 258903323..719158d1b 100755
--- a/newlib/libc/sys/tic80/configure
+++ b/newlib/libc/sys/tic80/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/tirtos/configure b/newlib/libc/sys/tirtos/configure
index a6e3dabd1..73407b954 100755
--- a/newlib/libc/sys/tirtos/configure
+++ b/newlib/libc/sys/tirtos/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/w65/configure b/newlib/libc/sys/w65/configure
index 4a33db611..925fd47ed 100755
--- a/newlib/libc/sys/w65/configure
+++ b/newlib/libc/sys/w65/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libc/sys/z8ksim/configure b/newlib/libc/sys/z8ksim/configure
index fd3337a78..01e808889 100755
--- a/newlib/libc/sys/z8ksim/configure
+++ b/newlib/libc/sys/z8ksim/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libm/configure b/newlib/libm/configure
index 42d503640..8932b51c1 100755
--- a/newlib/libm/configure
+++ b/newlib/libm/configure
@@ -768,6 +768,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 enable_shared
@@ -1417,6 +1418,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2879,6 +2881,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3725,8 +3739,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
@@ -11495,7 +11507,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11498 "configure"
+#line 11510 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11601,7 +11613,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11604 "configure"
+#line 11616 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/newlib/libm/machine/aarch64/configure b/newlib/libm/machine/aarch64/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libm/machine/aarch64/configure
+++ b/newlib/libm/machine/aarch64/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libm/machine/arm/configure b/newlib/libm/machine/arm/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libm/machine/arm/configure
+++ b/newlib/libm/machine/arm/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libm/machine/configure b/newlib/libm/machine/configure
index 2c237a126..758639f9b 100755
--- a/newlib/libm/machine/configure
+++ b/newlib/libm/machine/configure
@@ -3671,8 +3671,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
@@ -11441,7 +11439,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11444 "configure"
+#line 11442 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11547,7 +11545,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11550 "configure"
+#line 11548 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/newlib/libm/machine/i386/configure b/newlib/libm/machine/i386/configure
index 0d5fae926..7bf72e76a 100755
--- a/newlib/libm/machine/i386/configure
+++ b/newlib/libm/machine/i386/configure
@@ -760,6 +760,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 enable_shared
@@ -1408,6 +1409,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2815,6 +2817,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3661,8 +3675,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
@@ -11431,7 +11443,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11434 "configure"
+#line 11446 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11537,7 +11549,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11540 "configure"
+#line 11552 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/newlib/libm/machine/nds32/configure b/newlib/libm/machine/nds32/configure
index 43ea30a59..c3de10651 100644
--- a/newlib/libm/machine/nds32/configure
+++ b/newlib/libm/machine/nds32/configure
@@ -700,6 +700,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1341,6 +1342,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2512,6 +2514,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3358,8 +3372,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libm/machine/riscv/configure b/newlib/libm/machine/riscv/configure
index 397abd875..6a6ad6044 100755
--- a/newlib/libm/machine/riscv/configure
+++ b/newlib/libm/machine/riscv/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}
 
 
diff --git a/newlib/libm/machine/spu/configure b/newlib/libm/machine/spu/configure
index 397abd875..6a6ad6044 100644
--- a/newlib/libm/machine/spu/configure
+++ b/newlib/libm/machine/spu/configure
@@ -689,6 +689,7 @@ enable_newlib_iconv
 enable_newlib_elix_level
 enable_newlib_io_float
 enable_newlib_supplied_syscalls
+enable_newlib_fno_builtin
 enable_dependency_tracking
 enable_maintainer_mode
 '
@@ -1325,6 +1326,7 @@ Optional Features:
   --enable-newlib-elix-level         supply desired elix library level (1-4)
   --disable-newlib-io-float disable printf/scanf family float support
   --disable-newlib-supplied-syscalls disable newlib from supplying syscalls
+  --disable-newlib-fno-builtin disable -fno-builtin flag to allow compiler to use builtin library functions
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --enable-maintainer-mode  enable make rules and dependencies not useful
@@ -2489,6 +2491,18 @@ else
 fi
 
 
+# Check whether --enable-newlib-fno-builtin was given.
+if test "${enable_newlib_fno_builtin+set}" = set; then :
+  enableval=$enable_newlib_fno_builtin; case "${enableval}" in
+  yes) newlib_fno_builtin=yes ;;
+  no)  newlib_fno_builtin=no ;;
+  *)   as_fn_error $? "bad value ${enableval} for newlib-fno-builtin option" "$LINENO" 5 ;;
+ esac
+else
+  newlib_fno_builtin=
+fi
+
+
 
 test -z "${with_target_subdir}" && with_target_subdir=.
 
@@ -3335,8 +3349,6 @@ fi
 
 . ${newlib_basedir}/configure.host
 
-newlib_cflags="${newlib_cflags} -fno-builtin"
-
 NEWLIB_CFLAGS=${newlib_cflags}