From d49b2284b505e93cd415af4da3cd2cc2d3d168d3 Mon Sep 17 00:00:00 2001 From: Gilles Espinasse Date: Sat, 20 Oct 2012 20:22:51 +0200 Subject: [PATCH] configure: fix unrecognized -Wno option gcc-4.4 and later accept every -Wno option. So we can test for the option without no in the name to check if the option is supported. Each time a warning is emitted and without this fix, on gcc-4.4 that will add this warning: cc1: warning: unrecognized command line option "-Wno-unused-but-set-variable" bugs.freedesktop.org #51633, rediffed after 1.12.4 Of course this assumes that all compilers will behave like gcc, which is reasonably implicit in the set of warning flags. Signed-off-by: Gilles Espinasse [ickle: slight modification to test both -W and -Wno variants to ideally preserve compatability with non-GCC compilers sharing GCC options!] --- build/configure.ac.warnings | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/build/configure.ac.warnings b/build/configure.ac.warnings index 9b9c742a2..f984eb29c 100644 --- a/build/configure.ac.warnings +++ b/build/configure.ac.warnings @@ -21,8 +21,11 @@ MAYBE_WARN="-Wall -Wextra \ -Wno-missing-field-initializers -Wno-unused-parameter \ -Wno-attributes -Wno-long-long -Winline" +# New -Wno options should be added here +# gcc-4.4 and later accept every -Wno- option but may complain later that this +# option is unknow each time another warning happen. # -Wunused-but-set-variable is too noisy at present -NO_WARN="-Wno-unused-but-set-variable" +NO_WARN="unused-but-set-variable" dnl Sun Studio 12 likes to rag at us for abusing enums like dnl having cairo_status_t variables hold cairo_int_status_t @@ -48,8 +51,6 @@ MAYBE_WARN="$MAYBE_WARN -fno-strict-aliasing -fno-common" dnl Also to turn various gcc/glibc-specific preprocessor checks MAYBE_WARN="$MAYBE_WARN -Wp,-D_FORTIFY_SOURCE=2" -MAYBE_WARN="$MAYBE_WARN $NO_WARN" - # invalidate cached value if MAYBE_WARN has changed if test "x$cairo_cv_warn_maybe" != "x$MAYBE_WARN"; then unset cairo_cv_warn_cflags @@ -72,7 +73,9 @@ AC_CACHE_CHECK([for supported warning flags], cairo_cv_warn_cflags, [ for W in $MAYBE_WARN; do CAIRO_CC_TRY_FLAG([$W],, [WARN_CFLAGS="$WARN_CFLAGS $W"]) done - + for W in $NO_WARN; do + CAIRO_CC_TRY_FLAG([-W$W -Wno-$W],, [WARN_CFLAGS="$WARN_CFLAGS -Wno-$W"]) + done cairo_cv_warn_cflags=$WARN_CFLAGS cairo_cv_warn_maybe=$MAYBE_WARN