libm: Control errno support with _IEEE_LIBM configuration parameter

This removes the run-time configuration of errno support present in
portions of the math library and unifies all of the compile-time errno
configuration under a single parameter so that the whole library
is consistent.

The run-time support provided by _LIB_VERSION is no longer present in
the public API, although it is still used internally to disable errno
setting in some functions. Now that it is a constant, the compiler should
remove that code when errno is not supported.

This removes s_lib_ver.c as _LIB_VERSION is no longer variable.

Signed-off-by: Keith Packard <keithp@keithp.com>

5 files changed, 22 insertions, 57 deletions

diff --git a/newlib/libm/common/Makefile.am b/newlib/libm/common/Makefile.am
index 1eef0236a..1d178da4d 100644
--- a/newlib/libm/common/Makefile.am
+++ b/newlib/libm/common/Makefile.am
@@ -8,7 +8,7 @@ src = 	s_finite.c s_copysign.c s_modf.c s_scalbn.c \
 	s_cbrt.c s_exp10.c s_expm1.c s_ilogb.c \
 	s_infinity.c s_isinf.c s_isinfd.c s_isnan.c s_isnand.c \
 	s_log1p.c s_nan.c s_nextafter.c s_pow10.c \
-	s_rint.c s_logb.c s_log2.c s_lib_ver.c \
+	s_rint.c s_logb.c s_log2.c \
 	s_fdim.c s_fma.c s_fmax.c s_fmin.c s_fpclassify.c \
 	s_lrint.c s_llrint.c \
 	s_lround.c s_llround.c s_nearbyint.c s_remquo.c s_round.c s_scalbln.c \
diff --git a/newlib/libm/common/Makefile.in b/newlib/libm/common/Makefile.in
index 2caf7dd6c..896843833 100644
--- a/newlib/libm/common/Makefile.in
+++ b/newlib/libm/common/Makefile.in
@@ -85,19 +85,19 @@ am__objects_1 = lib_a-s_finite.$(OBJEXT) lib_a-s_copysign.$(OBJEXT) \
 	lib_a-s_nan.$(OBJEXT) lib_a-s_nextafter.$(OBJEXT) \
 	lib_a-s_pow10.$(OBJEXT) lib_a-s_rint.$(OBJEXT) \
 	lib_a-s_logb.$(OBJEXT) lib_a-s_log2.$(OBJEXT) \
-	lib_a-s_lib_ver.$(OBJEXT) lib_a-s_fdim.$(OBJEXT) \
-	lib_a-s_fma.$(OBJEXT) lib_a-s_fmax.$(OBJEXT) \
-	lib_a-s_fmin.$(OBJEXT) lib_a-s_fpclassify.$(OBJEXT) \
-	lib_a-s_lrint.$(OBJEXT) lib_a-s_llrint.$(OBJEXT) \
-	lib_a-s_lround.$(OBJEXT) lib_a-s_llround.$(OBJEXT) \
-	lib_a-s_nearbyint.$(OBJEXT) lib_a-s_remquo.$(OBJEXT) \
-	lib_a-s_round.$(OBJEXT) lib_a-s_scalbln.$(OBJEXT) \
-	lib_a-s_signbit.$(OBJEXT) lib_a-s_trunc.$(OBJEXT) \
-	lib_a-exp.$(OBJEXT) lib_a-exp2.$(OBJEXT) \
-	lib_a-exp_data.$(OBJEXT) lib_a-math_err.$(OBJEXT) \
-	lib_a-log.$(OBJEXT) lib_a-log_data.$(OBJEXT) \
-	lib_a-log2.$(OBJEXT) lib_a-log2_data.$(OBJEXT) \
-	lib_a-pow.$(OBJEXT) lib_a-pow_log_data.$(OBJEXT)
+	lib_a-s_fdim.$(OBJEXT) lib_a-s_fma.$(OBJEXT) \
+	lib_a-s_fmax.$(OBJEXT) lib_a-s_fmin.$(OBJEXT) \
+	lib_a-s_fpclassify.$(OBJEXT) lib_a-s_lrint.$(OBJEXT) \
+	lib_a-s_llrint.$(OBJEXT) lib_a-s_lround.$(OBJEXT) \
+	lib_a-s_llround.$(OBJEXT) lib_a-s_nearbyint.$(OBJEXT) \
+	lib_a-s_remquo.$(OBJEXT) lib_a-s_round.$(OBJEXT) \
+	lib_a-s_scalbln.$(OBJEXT) lib_a-s_signbit.$(OBJEXT) \
+	lib_a-s_trunc.$(OBJEXT) lib_a-exp.$(OBJEXT) \
+	lib_a-exp2.$(OBJEXT) lib_a-exp_data.$(OBJEXT) \
+	lib_a-math_err.$(OBJEXT) lib_a-log.$(OBJEXT) \
+	lib_a-log_data.$(OBJEXT) lib_a-log2.$(OBJEXT) \
+	lib_a-log2_data.$(OBJEXT) lib_a-pow.$(OBJEXT) \
+	lib_a-pow_log_data.$(OBJEXT)
 am__objects_2 = lib_a-sf_finite.$(OBJEXT) lib_a-sf_copysign.$(OBJEXT) \
 	lib_a-sf_modf.$(OBJEXT) lib_a-sf_scalbn.$(OBJEXT) \
 	lib_a-sf_cbrt.$(OBJEXT) lib_a-sf_exp10.$(OBJEXT) \
@@ -163,7 +163,7 @@ am__objects_5 = s_finite.lo s_copysign.lo s_modf.lo s_scalbn.lo \
 	s_cbrt.lo s_exp10.lo s_expm1.lo s_ilogb.lo s_infinity.lo \
 	s_isinf.lo s_isinfd.lo s_isnan.lo s_isnand.lo s_log1p.lo \
 	s_nan.lo s_nextafter.lo s_pow10.lo s_rint.lo s_logb.lo \
-	s_log2.lo s_lib_ver.lo s_fdim.lo s_fma.lo s_fmax.lo s_fmin.lo \
+	s_log2.lo s_fdim.lo s_fma.lo s_fmax.lo s_fmin.lo \
 	s_fpclassify.lo s_lrint.lo s_llrint.lo s_lround.lo \
 	s_llround.lo s_nearbyint.lo s_remquo.lo s_round.lo \
 	s_scalbln.lo s_signbit.lo s_trunc.lo exp.lo exp2.lo \
@@ -354,7 +354,7 @@ src = s_finite.c s_copysign.c s_modf.c s_scalbn.c \
 	s_cbrt.c s_exp10.c s_expm1.c s_ilogb.c \
 	s_infinity.c s_isinf.c s_isinfd.c s_isnan.c s_isnand.c \
 	s_log1p.c s_nan.c s_nextafter.c s_pow10.c \
-	s_rint.c s_logb.c s_log2.c s_lib_ver.c \
+	s_rint.c s_logb.c s_log2.c \
 	s_fdim.c s_fma.c s_fmax.c s_fmin.c s_fpclassify.c \
 	s_lrint.c s_llrint.c \
 	s_lround.c s_llround.c s_nearbyint.c s_remquo.c s_round.c s_scalbln.c \
@@ -602,12 +602,6 @@ lib_a-s_log2.o: s_log2.c
 lib_a-s_log2.obj: s_log2.c
 	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-s_log2.obj `if test -f 's_log2.c'; then $(CYGPATH_W) 's_log2.c'; else $(CYGPATH_W) '$(srcdir)/s_log2.c'; fi`
 
-lib_a-s_lib_ver.o: s_lib_ver.c
-	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-s_lib_ver.o `test -f 's_lib_ver.c' || echo '$(srcdir)/'`s_lib_ver.c
-
-lib_a-s_lib_ver.obj: s_lib_ver.c
-	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-s_lib_ver.obj `if test -f 's_lib_ver.c'; then $(CYGPATH_W) 's_lib_ver.c'; else $(CYGPATH_W) '$(srcdir)/s_lib_ver.c'; fi`
-
 lib_a-s_fdim.o: s_fdim.c
 	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-s_fdim.o `test -f 's_fdim.c' || echo '$(srcdir)/'`s_fdim.c
 
diff --git a/newlib/libm/common/fdlibm.h b/newlib/libm/common/fdlibm.h
index 8dfff243d..8dffc832d 100644
--- a/newlib/libm/common/fdlibm.h
+++ b/newlib/libm/common/fdlibm.h
@@ -15,6 +15,7 @@
 #include <math.h>
 #include <sys/types.h>
 #include <machine/ieeefp.h>
+#include "math_config.h"
 
 /* Most routines need to check whether a float is finite, infinite, or not a
    number, and many need to know whether the result of an operation will
diff --git a/newlib/libm/common/math_config.h b/newlib/libm/common/math_config.h
index 3be7e6320..1089b0ec6 100644
--- a/newlib/libm/common/math_config.h
+++ b/newlib/libm/common/math_config.h
@@ -38,15 +38,20 @@
 #endif
 #ifdef _IEEE_LIBM
 # define WANT_ERRNO 0
+# define _LIB_VERSION _IEEE_
 #else
 /* Set errno according to ISO C with (math_errhandling & MATH_ERRNO) != 0.  */
 # define WANT_ERRNO 1
+# define _LIB_VERSION _POSIX_
 #endif
 #ifndef WANT_ERRNO_UFLOW
 /* Set errno to ERANGE if result underflows to 0 (in all rounding modes).  */
 # define WANT_ERRNO_UFLOW (WANT_ROUNDING && WANT_ERRNO)
 #endif
 
+#define _IEEE_  -1
+#define _POSIX_ 0
+
 /* Compiler can inline round as a single instruction.  */
 #ifndef HAVE_FAST_ROUND
 # if __aarch64__
diff --git a/newlib/libm/common/s_lib_ver.c b/newlib/libm/common/s_lib_ver.c
deleted file mode 100644
index 8da03b79a..000000000
--- a/newlib/libm/common/s_lib_ver.c
+++ /dev/null
@@ -1,35 +0,0 @@
-
-/* @(#)s_lib_ver.c 5.1 93/09/24 */
-/*
- * ====================================================
- * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
- *
- * Developed at SunPro, a Sun Microsystems, Inc. business.
- * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice 
- * is preserved.
- * ====================================================
- */
-
-/*
- * MACRO for standards
- */
-
-#include "fdlibm.h"
-
-/*
- * define and initialize _LIB_VERSION
- */
-#ifdef _POSIX_MODE
-_LIB_VERSION_TYPE _LIB_VERSION = _POSIX_;
-#else
-#ifdef _XOPEN_MODE
-#error _XOPEN_MODE is unsupported
-#else
-#ifdef _SVID3_MODE
-#error _SVID3_MODE is unsupported
-#else					/* default _IEEE_MODE */
-_LIB_VERSION_TYPE _LIB_VERSION = _IEEE_;
-#endif
-#endif
-#endif