Re: [libvirt] [PATCH 1/6] Use gnulib's manywarnings & warnings modules

Remove custom code for checking compiler warnings, using gl_WARN_ADD instead. Don't list all flags ourselves, use gnulib's gl_MANYWARN_ALL_GCC to get all possible GCC flags, then turn off the ones we don't want yet. * acinclude.m4: Rewrite to use gl_WARN_ADD and gl_MANYWARN_ALL_GCC * bootstrap.conf: Add warnings & manywarnings * configure.ac: Switch to gl_WARN_ADD * m4/compiler-flags.m4: Obsoleted by gl_WARN_ADD --- acinclude.m4 | 158 +++++++++++++++++++++++++++----------------------- bootstrap.conf | 2 + configure.ac | 15 +++-- m4/compiler-flags.m4 | 48 --------------- 4 files changed, 96 insertions(+), 127 deletions(-) delete mode 100644 m4/compiler-flags.m4

+ + # List of warnings that are not relevant / wanted + dontwarn="$dontwarn -Wc++-compat" # Don't care about C++ compiler compat + dontwarn="$dontwarn -Wtraditional" # Don't care about ancient C standard compat + dontwarn="$dontwarn -Wtraditional-conversion" # Don't care about ancient C standard compat + dontwarn="$dontwarn -Wsystem-headers" # Ignore warnings in /usr/include + dontwarn="$dontwarn -Wpadded" # Happy for compiler to add struct padding + dontwarn="$dontwarn -Wunreachable-code" # GCC very confused with -O2 + dontwarn="$dontwarn -Wconversion" # Too many to deal with + dontwarn="$dontwarn -Wsign-conversion" # Too many to deal with + dontwarn="$dontwarn -Wvla" # GNULIB gettext.h violates + dontwarn="$dontwarn -Wundef" # Many GNULIB violations + dontwarn="$dontwarn -Wcast-qual" # Need to allow bad cast for execve() + dontwarn="$dontwarn -Wlong-long" # We need to use long long in many places + dontwarn="$dontwarn -Wswitch-default" # We allow manual list of all enum cases without default: + dontwarn="$dontwarn -Wswitch-enum" # We allow optional default: instead of listing all enum values + dontwarn="$dontwarn -Wstrict-overflow" # Not a problem since we don't use -fstrict-overflow + dontwarn="$dontwarn -Wunsafe-loop-optimizations" # Not a problem since we don't use -funsafe-loop-optimizations

+ + # We might fundamentally need some of these disabled forever, but ideally + # we'd turn many of them on + dontwarn="$dontwarn -Wformat-nonliteral"

+ dontwarn="$dontwarn -Wfloat-equal" + dontwarn="$dontwarn -Wdeclaration-after-statement"

+ dontwarn="$dontwarn -Wcast-qual" + dontwarn="$dontwarn -Wconversion" + dontwarn="$dontwarn -Wsign-conversion" + dontwarn="$dontwarn -Wold-style-definition" + dontwarn="$dontwarn -Wmissing-noreturn" + dontwarn="$dontwarn -Wpacked" + dontwarn="$dontwarn -Wunused-macros" + dontwarn="$dontwarn -Woverlength-strings" + dontwarn="$dontwarn -Wmissing-format-attribute" + dontwarn="$dontwarn -Wstack-protector"

+ + # Get all possible GCC warnings + gl_MANYWARN_ALL_GCC([maybewarn]) + + # Remove the ones we don't want, blacklisted earlier + gl_MANYWARN_COMPLEMENT([wantwarn], [$maybewarn], [$dontwarn]) + + # Check for $CC support of each warning + for w in $wantwarn; do + gl_WARN_ADD([$w]) + done + + # GNULIB uses '-W' which includes a bunch of stuff, + # kinda like -Wextra. Unfortunately, it means you

+ # can't simply use '-Wsign-compare' with gl_MANYWARN_COMPLEMENT + # So we have -W enabled, and then have to explicitly turn off + gl_WARN_ADD(-Wno-sign-compare) + + # This should be < 256 really, but with PATH_MAX everywhere + # we have doom, even with 4096. In fact we have some functions + # with several PATH_MAX sized variables :-( We should kill off + # all PATH_MAX usage and then lower this limit + gl_WARN_ADD([-Wframe-larger-than=65700]) + dnl gl_WARN_ADD([-Wframe-larger-than=4096]) + dnl gl_WARN_ADD([-Wframe-larger-than=256]) + + # Extra special flags + gl_WARN_ADD([-Wp,-D_FORTIFY_SOURCE=2]) + dnl Fedora only uses -fstack-protector, but doesn't seem to + dnl be great overhead in adding -fstack-protector-all instead + dnl gl_WARN_ADD([-fstack-protector]) + gl_WARN_ADD([-fstack-protector-all]) + gl_WARN_ADD([--param=ssp-buffer-size=4]) + gl_WARN_ADD([-fexceptions]) + gl_WARN_ADD([-fasynchronous-unwind-tables]) + gl_WARN_ADD([-fdiagnostics-show-option]) + + if test "$enable_compile_warnings" = "error" + then + gl_WARN_ADD([-Werror]) + fi

@@ -81,6 +82,7 @@ timegm uname useless-if-before-free usleep +warnings vasprintf verify vc-list-files

diff --git a/configure.ac b/configure.ac index a8d223a..7874c30 100644 --- a/configure.ac +++ b/configure.ac @@ -1970,12 +1970,14 @@ AC_ARG_ENABLE([test-coverage], enable_coverage=$enableval if test "${enable_coverage}" = yes; then - COMPILER_FLAGS= - gl_COMPILER_FLAGS(-fprofile-arcs) - gl_COMPILER_FLAGS(-ftest-coverage) - AC_SUBST([COVERAGE_CFLAGS], [$COMPILER_FLAGS]) - AC_SUBST([COVERAGE_LDFLAGS], [$COMPILER_FLAGS]) - COMPILER_FLAGS= + save_WARN_CFLAGS=$WARN_CFLAGS + WARN_CFLAGS= + gl_WARN_ADD(-fprofile-arcs) + gl_WARN_ADD(-ftest-coverage)