3 dnl Copyright (C) 2008-2024 Free Software Foundation, Inc.
4 dnl This file is free software; the Free Software Foundation
5 dnl gives unlimited permission to copy and/or distribute it,
6 dnl with or without modifications, as long as this notice is preserved.
8 # Implementation of the specialization of gl_MANYWARN_ALL_GCC
10 AC_DEFUN([gl_MANYWARN_ALL_GCC_CXX_IMPL],
14 dnl First, check for some issues that only occur when combining multiple
15 dnl gcc warning categories.
16 AC_REQUIRE([AC_PROG_CXX])
17 if test -n "$GXX"; then
19 dnl Check if -W -Werror -Wno-missing-field-initializers is supported
20 dnl with the current $CXX $CXXFLAGS $CPPFLAGS.
21 AC_CACHE_CHECK([whether -Wno-missing-field-initializers is supported],
22 [gl_cv_cxx_nomfi_supported],
23 [gl_saved_CXXFLAGS="$CXXFLAGS"
24 CXXFLAGS="$CXXFLAGS -W -Werror -Wno-missing-field-initializers"
26 [AC_LANG_PROGRAM([[]], [[]])],
27 [gl_cv_cxx_nomfi_supported=yes],
28 [gl_cv_cxx_nomfi_supported=no])
29 CXXFLAGS="$gl_saved_CXXFLAGS"
32 if test "$gl_cv_cxx_nomfi_supported" = yes; then
33 dnl Now check whether -Wno-missing-field-initializers is needed
34 dnl for the { 0, } construct.
35 AC_CACHE_CHECK([whether -Wno-missing-field-initializers is needed],
36 [gl_cv_cxx_nomfi_needed],
37 [gl_saved_CXXFLAGS="$CXXFLAGS"
38 CXXFLAGS="$CXXFLAGS -W -Werror"
43 typedef struct { int a; int b; } s_t;
49 [gl_cv_cxx_nomfi_needed=no],
50 [gl_cv_cxx_nomfi_needed=yes])
51 CXXFLAGS="$gl_saved_CXXFLAGS"
55 dnl Next, check if -Werror -Wuninitialized is useful with the
56 dnl user's choice of $CXXFLAGS; some versions of gcc warn that it
57 dnl has no effect if -O is not also used
58 AC_CACHE_CHECK([whether -Wuninitialized is supported],
59 [gl_cv_cxx_uninitialized_supported],
60 [gl_saved_CXXFLAGS="$CXXFLAGS"
61 CXXFLAGS="$CXXFLAGS -Werror -Wuninitialized"
63 [AC_LANG_PROGRAM([[]], [[]])],
64 [gl_cv_cxx_uninitialized_supported=yes],
65 [gl_cv_cxx_uninitialized_supported=no])
66 CXXFLAGS="$gl_saved_CXXFLAGS"
71 # List all gcc warning categories.
72 # To compare this list to your installed GCC's, run this Bash command:
75 # <(sed -n 's/^ *\(-[^ ]*\) .*/\1/p' manywarnings-c++.m4 | sort) \
76 # <(gcc --help=warnings | sed -n 's/^ \(-[^ ]*\) .*/\1/p' | sort |
78 # awk '/^[^#]/ {print $1}' ../build-aux/g++-warning.spec))
81 for gl_manywarn_item in \
85 -Waggressive-loop-optimizations \
89 -Wbuiltin-macro-redefined \
95 -Wconditionally-supported \
101 -Wdelete-incomplete \
102 -Wdelete-non-virtual-dtor \
104 -Wdeprecated-declarations \
105 -Wdisabled-optimization \
113 -Wformat-contains-nul \
114 -Wformat-extra-args \
115 -Wformat-nonliteral \
117 -Wformat-signedness \
119 -Wformat-zero-length \
120 -Wfree-nonheap-object \
121 -Wignored-qualifiers \
122 -Winherited-variadic-ctor \
125 -Wint-to-pointer-cast \
126 -Winvalid-memory-model \
130 -Wlogical-not-parentheses \
133 -Wmaybe-uninitialized \
134 -Wmemset-transposed-args \
136 -Wmissing-declarations \
137 -Wmissing-field-initializers \
138 -Wmissing-include-dirs \
142 -Wnon-template-friend \
149 -Woverlength-strings \
150 -Woverloaded-virtual \
152 -Wpacked-bitfield-compat \
158 -Wreturn-local-addr \
162 -Wshift-count-negative \
163 -Wshift-count-overflow \
165 -Wsized-deallocation \
166 -Wsizeof-array-argument \
167 -Wsizeof-pointer-memaccess \
170 -Wstrict-null-sentinel \
172 -Wsuggest-attribute=const \
173 -Wsuggest-attribute=format \
174 -Wsuggest-attribute=noreturn \
175 -Wsuggest-attribute=pure \
176 -Wsuggest-final-methods \
177 -Wsuggest-final-types \
187 -Wunsafe-loop-optimizations \
189 -Wunused-but-set-parameter \
190 -Wunused-but-set-variable \
193 -Wunused-local-typedefs \
202 -Wvector-operation-performance \
203 -Wvirtual-move-assign \
205 -Wvolatile-register-var \
207 -Wzero-as-null-pointer-constant \
210 gl_manywarn_set="$gl_manywarn_set $gl_manywarn_item"
213 # gcc --help=warnings outputs an unusual form for these options; list
214 # them here so that the above 'comm' command doesn't report a false match.
215 gl_manywarn_set="$gl_manywarn_set -Warray-bounds=2"
216 gl_manywarn_set="$gl_manywarn_set -Wnormalized=nfc"
217 gl_manywarn_set="$gl_manywarn_set -Wshift-overflow=2"
218 gl_manywarn_set="$gl_manywarn_set -Wunused-const-variable=2"
220 # These are needed for older GCC versions.
221 if test -n "$GXX"; then
222 case `($CXX --version) 2>/dev/null` in
223 'g++ (GCC) '[[0-3]].* | \
224 'g++ (GCC) '4.[[0-7]].*)
225 gl_manywarn_set="$gl_manywarn_set -fdiagnostics-show-option"
226 gl_manywarn_set="$gl_manywarn_set -funit-at-a-time"
231 # Disable specific options as needed.
232 if test "$gl_cv_cxx_nomfi_needed" = yes; then
233 gl_manywarn_set="$gl_manywarn_set -Wno-missing-field-initializers"
236 if test "$gl_cv_cxx_uninitialized_supported" = no; then
237 gl_manywarn_set="$gl_manywarn_set -Wno-uninitialized"