diff options
Diffstat (limited to 'configure.ac')
-rw-r--r-- | configure.ac | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/configure.ac b/configure.ac index 5e9cb6c7..bb0559a1 100644 --- a/configure.ac +++ b/configure.ac @@ -366,6 +366,26 @@ AC_ARG_WITH([kernel-source], [kernel_source="$with_kernel_source"]) AC_SUBST(kernel_source) +dnl Add flags for gcc and g++ +if test "x$GCC" = xyes; then + # Enable -fvisibility=hidden if using a gcc that supports it + save_CFLAGS="$CFLAGS" + AC_MSG_CHECKING([whether $CC supports -fvisibility=hidden]) + VISIBILITY_CFLAGS="-fvisibility=hidden" + CFLAGS="$CFLAGS $VISIBILITY_CFLAGS" + AC_LINK_IFELSE([AC_LANG_PROGRAM()], AC_MSG_RESULT([yes]), + [VISIBILITY_CFLAGS=""; AC_MSG_RESULT([no])]); + + # Restore CFLAGS; VISIBILITY_CFLAGS are added to it where needed. + CFLAGS=$save_CFLAGS + + if test "x$VISIBILITY_CFLAGS" != x; then + AC_DEFINE(HAVE_VISIBILITY, 1, [Compiler has -fvisibility support]) + fi + + AC_SUBST([VISIBILITY_CFLAGS]) +fi + AC_SUBST(WARN_CFLAGS) AC_CONFIG_FILES([ Makefile |