blob: 30b6204bb70975a3e4af303a9d9378fcc37f862e [file] [log] [blame]
# manywarnings-c++.m4 serial 3
dnl Copyright (C) 2008-2019 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
# Implementation of the specialization of gl_MANYWARN_ALL_GCC
# for _AC_LANG = C++.
AC_DEFUN([gl_MANYWARN_ALL_GCC_CXX_IMPL],
[
AC_LANG_PUSH([C++])
dnl First, check for some issues that only occur when combining multiple
dnl gcc warning categories.
AC_REQUIRE([AC_PROG_CXX])
if test -n "$GXX"; then
dnl Check if -W -Werror -Wno-missing-field-initializers is supported
dnl with the current $CXX $CXXFLAGS $CPPFLAGS.
AC_CACHE_CHECK([whether -Wno-missing-field-initializers is supported],
[gl_cv_cxx_nomfi_supported],
[gl_save_CXXFLAGS="$CXXFLAGS"
CXXFLAGS="$CXXFLAGS -W -Werror -Wno-missing-field-initializers"
AC_COMPILE_IFELSE(
[AC_LANG_PROGRAM([[]], [[]])],
[gl_cv_cxx_nomfi_supported=yes],
[gl_cv_cxx_nomfi_supported=no])
CXXFLAGS="$gl_save_CXXFLAGS"
])
if test "$gl_cv_cxx_nomfi_supported" = yes; then
dnl Now check whether -Wno-missing-field-initializers is needed
dnl for the { 0, } construct.
AC_CACHE_CHECK([whether -Wno-missing-field-initializers is needed],
[gl_cv_cxx_nomfi_needed],
[gl_save_CXXFLAGS="$CXXFLAGS"
CXXFLAGS="$CXXFLAGS -W -Werror"
AC_COMPILE_IFELSE(
[AC_LANG_PROGRAM(
[[int f (void)
{
typedef struct { int a; int b; } s_t;
s_t s1 = { 0, };
return s1.b;
}
]],
[[]])],
[gl_cv_cxx_nomfi_needed=no],
[gl_cv_cxx_nomfi_needed=yes])
CXXFLAGS="$gl_save_CXXFLAGS"
])
fi
dnl Next, check if -Werror -Wuninitialized is useful with the
dnl user's choice of $CXXFLAGS; some versions of gcc warn that it
dnl has no effect if -O is not also used
AC_CACHE_CHECK([whether -Wuninitialized is supported],
[gl_cv_cxx_uninitialized_supported],
[gl_save_CXXFLAGS="$CXXFLAGS"
CXXFLAGS="$CXXFLAGS -Werror -Wuninitialized"
AC_COMPILE_IFELSE(
[AC_LANG_PROGRAM([[]], [[]])],
[gl_cv_cxx_uninitialized_supported=yes],
[gl_cv_cxx_uninitialized_supported=no])
CXXFLAGS="$gl_save_CXXFLAGS"
])
fi
# List all gcc warning categories.
# To compare this list to your installed GCC's, run this Bash command:
#
# comm -3 \
# <(sed -n 's/^ *\(-[^ ]*\) .*/\1/p' manywarnings-c++.m4 | sort) \
# <(gcc --help=warnings | sed -n 's/^ \(-[^ ]*\) .*/\1/p' | sort |
# grep -v -x -f <(
# awk '/^[^#]/ {print $1}' ../build-aux/g++-warning.spec))
gl_manywarn_set=
for gl_manywarn_item in \
-W \
-Wabi \
-Wabi-tag \
-Waddress \
-Waggressive-loop-optimizations \
-Wall \
-Wattributes \
-Wbool-compare \
-Wbuiltin-macro-redefined \
-Wcast-align \
-Wchar-subscripts \
-Wchkp \
-Wclobbered \
-Wcomment \
-Wcomments \
-Wconditionally-supported \
-Wconversion-null \
-Wcoverage-mismatch \
-Wcpp \
-Wctor-dtor-privacy \
-Wdate-time \
-Wdelete-incomplete \
-Wdelete-non-virtual-dtor \
-Wdeprecated \
-Wdeprecated-declarations \
-Wdisabled-optimization \
-Wdiv-by-zero \
-Wdouble-promotion \
-Weffc++ \
-Wempty-body \
-Wendif-labels \
-Wenum-compare \
-Wextra \
-Wformat-contains-nul \
-Wformat-extra-args \
-Wformat-nonliteral \
-Wformat-security \
-Wformat-signedness \
-Wformat-y2k \
-Wformat-zero-length \
-Wfree-nonheap-object \
-Wignored-qualifiers \
-Winherited-variadic-ctor \
-Winit-self \
-Winline \
-Wint-to-pointer-cast \
-Winvalid-memory-model \
-Winvalid-offsetof \
-Winvalid-pch \
-Wliteral-suffix \
-Wlogical-not-parentheses \
-Wlogical-op \
-Wmain \
-Wmaybe-uninitialized \
-Wmemset-transposed-args \
-Wmissing-braces \
-Wmissing-declarations \
-Wmissing-field-initializers \
-Wmissing-include-dirs \
-Wmultichar \
-Wnarrowing \
-Wnoexcept \
-Wnon-template-friend \
-Wnon-virtual-dtor \
-Wnonnull \
-Wodr \
-Wold-style-cast \
-Wopenmp-simd \
-Woverflow \
-Woverlength-strings \
-Woverloaded-virtual \
-Wpacked \
-Wpacked-bitfield-compat \
-Wparentheses \
-Wpmf-conversions \
-Wpointer-arith \
-Wpragmas \
-Wreorder \
-Wreturn-local-addr \
-Wreturn-type \
-Wsequence-point \
-Wshadow \
-Wshift-count-negative \
-Wshift-count-overflow \
-Wsign-promo \
-Wsized-deallocation \
-Wsizeof-array-argument \
-Wsizeof-pointer-memaccess \
-Wstack-protector \
-Wstrict-aliasing \
-Wstrict-null-sentinel \
-Wstrict-overflow \
-Wsuggest-attribute=const \
-Wsuggest-attribute=format \
-Wsuggest-attribute=noreturn \
-Wsuggest-attribute=pure \
-Wsuggest-final-methods \
-Wsuggest-final-types \
-Wsuggest-override \
-Wswitch \
-Wswitch-bool \
-Wsync-nand \
-Wsystem-headers \
-Wtrampolines \
-Wtrigraphs \
-Wtype-limits \
-Wuninitialized \
-Wunknown-pragmas \
-Wunsafe-loop-optimizations \
-Wunused \
-Wunused-but-set-parameter \
-Wunused-but-set-variable \
-Wunused-function \
-Wunused-label \
-Wunused-local-typedefs \
-Wunused-macros \
-Wunused-parameter \
-Wunused-result \
-Wunused-value \
-Wunused-variable \
-Wuseless-cast \
-Wvarargs \
-Wvariadic-macros \
-Wvector-operation-performance \
-Wvirtual-move-assign \
-Wvla \
-Wvolatile-register-var \
-Wwrite-strings \
-Wzero-as-null-pointer-constant \
\
; do
gl_manywarn_set="$gl_manywarn_set $gl_manywarn_item"
done
# gcc --help=warnings outputs an unusual form for these options; list
# them here so that the above 'comm' command doesn't report a false match.
gl_manywarn_set="$gl_manywarn_set -Warray-bounds=2"
gl_manywarn_set="$gl_manywarn_set -Wnormalized=nfc"
gl_manywarn_set="$gl_manywarn_set -Wshift-overflow=2"
gl_manywarn_set="$gl_manywarn_set -Wunused-const-variable=2"
# These are needed for older GCC versions.
if test -n "$GXX"; then
case `($CXX --version) 2>/dev/null` in
'g++ (GCC) '[[0-3]].* | \
'g++ (GCC) '4.[[0-7]].*)
gl_manywarn_set="$gl_manywarn_set -fdiagnostics-show-option"
gl_manywarn_set="$gl_manywarn_set -funit-at-a-time"
;;
esac
fi
# Disable specific options as needed.
if test "$gl_cv_cxx_nomfi_needed" = yes; then
gl_manywarn_set="$gl_manywarn_set -Wno-missing-field-initializers"
fi
if test "$gl_cv_cxx_uninitialized_supported" = no; then
gl_manywarn_set="$gl_manywarn_set -Wno-uninitialized"
fi
$1=$gl_manywarn_set
AC_LANG_POP([C++])
])