Makefile.flags: add a test for -lrt availability

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 8 insertions, 5 deletions

diff --git a/Makefile.flags b/Makefile.flags
index 3b02bfaac..667481983 100644
--- a/Makefile.flags
+++ b/Makefile.flags
@@ -145,18 +145,21 @@ CFLAGS += --sysroot=$(CONFIG_SYSROOT)
 export SYSROOT=$(CONFIG_SYSROOT)
 endif
 
+# libm may be needed for dc, awk, ntpd
+LDLIBS += m
 # Android has no separate crypt library
 # gcc-4.2.1 fails if we try to feed C source on stdin:
 #  echo 'int main(void){return 0;}' | $(CC) $(CFLAGS) -lcrypt -o /dev/null -xc -
 # fall back to using a temp file:
-CRYPT_AVAILABLE := $(shell echo 'int main(void){return 0;}' >crypttest.c; $(CC) $(CFLAGS) -lcrypt -o /dev/null crypttest.c >/dev/null 2>&1 && echo "y"; rm crypttest.c)
+CRYPT_AVAILABLE := $(shell echo 'int main(void){return 0;}' >bb_libtest.c; $(CC) $(CFLAGS) -lcrypt -o /dev/null bb_libtest.c >/dev/null 2>&1 && echo "y"; rm bb_libtest.c)
+RT_AVAILABLE    := $(shell echo 'int main(void){return 0;}' >bb_libtest.c; $(CC) $(CFLAGS) -lrt    -o /dev/null bb_libtest.c >/dev/null 2>&1 && echo "y"; rm bb_libtest.c)
 ifeq ($(CRYPT_AVAILABLE),y)
-LDLIBS += m rt crypt
-else
-LDLIBS += m rt
+LDLIBS += crypt
 endif
-# libm may be needed for dc, awk, ntpd
 # librt may be needed for clock_gettime()
+ifeq ($(RT_AVAILABLE),y)
+LDLIBS += rt
+endif
 
 # libpam may use libpthread, libdl and/or libaudit.
 # On some platforms that requires an explicit -lpthread, -ldl, -laudit.