The former does not imply the latter and vice-versa. One such example is
the Sun compiler.
v2: Add missing closing brakets. (Alan)
Cc: Alan Coopersmith <alan.coopersmith at oracle.com>
Cc: Thierry Reding <treding at nvidia.com>
Signed-off-by: Emil Velikov <emil.l.velikov at gmail.com>
---
configure.ac | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/configure.ac b/configure.ac
index 155d577..76cf91e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -415,12 +415,17 @@ if test "x$GCC" = xyes; then
# Restore CFLAGS; VISIBILITY_CFLAGS are added to it where needed.
CFLAGS=$save_CFLAGS
+ AC_SUBST([VISIBILITY_CFLAGS])
+fi
- if test "x$VISIBILITY_CFLAGS" != x; then
- AC_DEFINE(HAVE_VISIBILITY, 1, [Compiler has -fvisibility support])
- fi
+AC_MSG_CHECKING([whether $CC supports __attribute__((visibility))])
+AC_LINK_IFELSE([AC_LANG_PROGRAM([
+ int foo_default( void ) __attribute__((visibility("default")));
+ int foo_hidden( void ) __attribute__((visibility("hidden")));
+])], HAVE_ATTRIBUTE_VISIBILITY="yes"; AC_MSG_RESULT([yes]),
AC_MSG_RESULT([no]));
- AC_SUBST([VISIBILITY_CFLAGS])
+if test "x$HAVE_ATTRIBUTE_VISIBILITY" = xyes; then
+ AC_DEFINE(HAVE_VISIBILITY, 1, [Compiler supports
__attribute__((visibility))])
fi
AC_SUBST(WARN_CFLAGS)
--
2.3.1
