On Mon, Apr 04, 2011 at 02:29:06PM -0600, Eric Blake wrote:
On 04/04/2011 10:19 AM, Daniel P. Berrange wrote:
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
Seems okay (but long lines - any way to break that into 80 columns?)
+ + # We might fundamentally need some of these disabled forever, but ideally + # we'd turn many of them on + dontwarn="$dontwarn -Wformat-nonliteral"
This one may need to always be disabled, thanks to virAsprintf (it would be nicer if we could disable for just one or two files, rather than globally).
+ dontwarn="$dontwarn -Wfloat-equal" + dontwarn="$dontwarn -Wdeclaration-after-statement"
If gcc would do better, I'd love to guarantee C99 and take advantage of this (smaller scopes have maintenance benefits) - thus, I envision this one being permanent (float it up to the earlier set).
+ dontwarn="$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="$dontwarn -Wstack-protector"
Yes, I agree that the rest of these should be temporary, and are probably worth fixing.
+ + # Get all possible GCC warnings + gl_MANYWARN_ALL_GCC([maybewarn]) + + # Remove the ones we don't want, blacklisted earlier + gl_MANYWARN_COMPLEMENT([wantwarn], [$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
"kinda like"? Exactly like! -W was the old spelling, -Wextra was the new one (added quite some time ago; something like gcc 3.4, off the top of my head).
Ah, I didn't realize it was the same.
+ # 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
Looks like a good conversion.
I also added gl_WARN_ADD([-Wjump-misses-init]) because we loose that due to turning off -Wc++-compat Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|