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| author | Akim Demaille <akim@lrde.epita.fr> | 2012-12-07 09:58:40 +0100 |
|---|---|---|
| committer | Akim Demaille <akim@lrde.epita.fr> | 2012-12-07 10:16:47 +0100 |
| commit | 85a2f27fc4e271e992ca35561ae93c55aac21c07 (patch) | |
| tree | 632ef2c0c9cb1016a02896a43ccec4c28856f49c /configure.ac | |
| parent | 28d16d1f7cd7ae201d368210ba87f3ef5c0abd51 (diff) | |
| download | bison-85a2f27fc4e271e992ca35561ae93c55aac21c07.tar.gz | |
build: keep -Wmissing-declarations and -Wmissing-prototypes for modern GCCs
Fixes a -Werror failure of xalloc.h used in src.
From Eric Blake.
http://lists.gnu.org/archive/html/bug-gnulib/2012-12/msg00006.html
* configure.ac: Check whether GCC pragma diagnostic push/pop works.
Enable these warnings for bison if it does.
Enable these warnings for the test suite anyway.
Diffstat (limited to 'configure.ac')
| -rw-r--r-- | configure.ac | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/configure.ac b/configure.ac index 4004f559..d14cb29e 100644 --- a/configure.ac +++ b/configure.ac @@ -58,6 +58,20 @@ AC_PROG_CXX # Gnulib (early checks). gl_EARLY +# Gnulib uses '#pragma GCC diagnostic push' to silence some +# warnings, but older gcc doesn't support this. +AC_CACHE_CHECK([whether pragma GCC diagnostic push works], + [lv_cv_gcc_pragma_push_works], [ + save_CFLAGS=$CFLAGS + CFLAGS='-Wunknown-pragmas -Werror' + AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[ + #pragma GCC diagnostic push + #pragma GCC diagnostic pop + ]])], + [lv_cv_gcc_pragma_push_works=yes], + [lv_cv_gcc_pragma_push_works=no]) + CFLAGS=$save_CFLAGS]) + AC_ARG_ENABLE([gcc-warnings], [ --enable-gcc-warnings turn on lots of GCC warnings (not recommended)], [case $enable_gcc_warnings in @@ -68,8 +82,7 @@ AC_ARG_ENABLE([gcc-warnings], if test "$enable_gcc_warnings" = yes; then warn_common='-Wall -Wextra -Wno-sign-compare -Wcast-align -Wformat -Wpointer-arith -Wwrite-strings' - warn_c='-Wbad-function-cast -Wmissing-declarations -Wmissing-prototypes - -Wshadow -Wstrict-prototypes' + warn_c='-Wbad-function-cast -Wshadow -Wstrict-prototypes' warn_cxx='-Wnoexcept' AC_LANG_PUSH([C]) # Clang supports many of GCC's -W options, but only issues warnings @@ -89,12 +102,21 @@ if test "$enable_gcc_warnings" = yes; then gl_WARN_ADD([$i], [WARN_CFLAGS]) done gl_WARN_ADD([-Werror], [WERROR_CFLAGS]) + + # Warnings for the test suite, and maybe for bison if GCC is modern + # enough. + gl_WARN_ADD([-Wmissing-declarations], [WARN_CFLAGS_TEST]) + gl_WARN_ADD([-Wmissing-prototypes], [WARN_CFLAGS_TEST]) + test $lv_cv_gcc_pragma_push_works = yes && + AS_VAR_APPEND([WARN_CFLAGS], [" $WARN_CFLAGS_TEST"]) + # Warnings for the test suite only. gl_WARN_ADD([-Wundef], [WARN_CFLAGS_TEST]) gl_WARN_ADD([-pedantic], [WARN_CFLAGS_TEST]) CFLAGS=$save_CFLAGS AC_LANG_POP([C]) + AC_LANG_PUSH([C++]) save_CXXFLAGS=$CXXFLAGS gl_WARN_ADD([-Werror=unknown-warning-option], [CXXFLAGS]) |