mirror of
https://gitlab.freedesktop.org/cairo/cairo.git
synced 2025-12-20 04:40:07 +01:00
6d93bddbd6
Found via `codespell -i 3 -w -I ../cairo-word-whitelist.txt -L tim,ned,uint`
Follow up of 12cb59be7d
Reviewed-by: Bryce Harrington <bryce@bryceharrington.org>
99 lines
4.1 KiB
Text
99 lines
4.1 KiB
Text
dnl Use lots of warning flags with with gcc and compatible compilers
|
|
|
|
dnl Note: if you change the following variable, the cache is automatically
|
|
dnl skipped and all flags rechecked. So there's no need to do anything
|
|
dnl else. If for any reason you need to force a recheck, just change
|
|
dnl MAYBE_WARN in an ignorable way (like adding whitespace)
|
|
|
|
# -Wcast-align generates lots of false positive reports we need to
|
|
# cast image data from uint8_t to uin32_t.
|
|
|
|
# -Wlogical-op causes too much noise from strcmp("literal", str)
|
|
|
|
MAYBE_WARN="-Wall -Wextra \
|
|
-Wmissing-declarations -Werror-implicit-function-declaration \
|
|
-Wpointer-arith -Wwrite-strings -Wsign-compare -Wpacked \
|
|
-Wswitch-enum -Wmissing-format-attribute -Wvolatile-register-var \
|
|
-Wstrict-aliasing=2 -Winit-self -Wunsafe-loop-optimizations \
|
|
-Wno-missing-field-initializers -Wno-unused-parameter \
|
|
-Wno-attributes -Wno-long-long -Winline"
|
|
|
|
MAYBE_C_SPECIFIC_WARN="-Wold-style-definition \
|
|
-Wdeclaration-after-statement -Wstrict-prototypes \
|
|
-Wmissing-prototypes -Wbad-function-cast -Wnested-externs"
|
|
|
|
# New -Wno options should be added here
|
|
# gcc-4.4 and later accept every -Wno- option but may complain later that this
|
|
# option is unknown each time another warning happens.
|
|
# -Wunused-but-set-variable is too noisy at present
|
|
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
|
|
dnl values. It's bad, we know. Now please be quiet.
|
|
MAYBE_WARN="$MAYBE_WARN -erroff=E_ENUM_TYPE_MISMATCH_ARG \
|
|
-erroff=E_ENUM_TYPE_MISMATCH_OP"
|
|
|
|
dnl We also abuse the warning-flag facility to enable other compiler
|
|
dnl options. Namely, the following:
|
|
MAYBE_WARN="$MAYBE_WARN -fno-strict-aliasing -fno-common"
|
|
|
|
dnl Also to turn various gcc/glibc-specific preprocessor checks
|
|
MAYBE_WARN="$MAYBE_WARN -Wp,-D_FORTIFY_SOURCE=2"
|
|
|
|
# invalidate cached value if MAYBE_WARN has changed
|
|
if test "x$cairo_cv_warn_maybe" != "x$MAYBE_WARN"; then
|
|
unset cairo_cv_warn_cflags
|
|
fi
|
|
AC_CACHE_CHECK([for supported warning flags], cairo_cv_warn_cflags, [
|
|
echo
|
|
WARN_CFLAGS=""
|
|
|
|
# Some warning options are not supported by all versions of
|
|
# gcc, so test all desired options against the current
|
|
# compiler.
|
|
#
|
|
# Note that there are some order dependencies
|
|
# here. Specifically, an option that disables a warning will
|
|
# have no net effect if a later option then enables that
|
|
# warnings, (perhaps implicitly). So we put some grouped
|
|
# options (-Wall and -Wextra) up front and the -Wno options
|
|
# last.
|
|
|
|
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 $MAYBE_C_SPECIFIC_WARN"
|
|
|
|
AC_MSG_CHECKING([which warning flags were supported])
|
|
])
|
|
WARN_CFLAGS="$cairo_cv_warn_cflags"
|
|
CAIRO_CFLAGS="$CAIRO_CFLAGS $WARN_CFLAGS"
|
|
|
|
# We only wish to enable attribute(warn_unused_result) if we can prevent
|
|
# gcc from generating thousands of warnings about the misapplication of the
|
|
# attribute to void functions and variables.
|
|
AC_CACHE_CHECK([how to enable unused result warnings], cairo_cv_warn_unused_result, [
|
|
AC_REQUIRE([AC_PROG_GREP])
|
|
cairo_cv_warn_unused_result=""
|
|
if echo $WARN_CFLAGS | $GREP -e '-Wno-attributes' >/dev/null; then
|
|
CAIRO_CC_TRY_FLAG_SILENT(
|
|
[-Wno-attributes],
|
|
[__attribute__((__warn_unused_result__)) void f (void) {}
|
|
__attribute__((__warn_unused_result__)) int g;],
|
|
[cairo_cv_warn_unused_result="__attribute__((__warn_unused_result__))"])
|
|
fi
|
|
])
|
|
AC_DEFINE_UNQUOTED([WARN_UNUSED_RESULT], [$cairo_cv_warn_unused_result],
|
|
[Define to the value your compiler uses to support the warn-unused-result attribute])
|
|
|
|
dnl check linker flags
|
|
AC_CACHE_CHECK([how to allow undefined symbols in shared libraries used by test suite], cairo_cv_test_undefined_ldflags,
|
|
[CAIRO_CC_TRY_FLAG_SILENT([-Wl,--allow-shlib-undefined], [],
|
|
[cairo_cv_test_undefined_ldflags="-Wl,--allow-shlib-undefined]")])
|
|
CAIRO_TEST_UNDEFINED_LDFLAGS="$cairo_cv_test_undefined_ldflags"
|
|
AC_SUBST(CAIRO_TEST_UNDEFINED_LDFLAGS)
|