-# manywarnings.m4 serial 1
-dnl Copyright (C) 2008, 2009, 2010 Free Software Foundation, Inc.
+# manywarnings.m4 serial 13
+dnl Copyright (C) 2008-2018 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.
# gl_MANYWARN_ALL_GCC(VARIABLE)
# -----------------------------
-# Add all documented GCC (currently as per version 4.4) warning
-# parameters to variable VARIABLE. Note that you need to test them
-# using gl_WARN_ADD if you want to make sure your gcc understands it.
+# Add all documented GCC warning parameters to variable VARIABLE.
+# Note that you need to test them using gl_WARN_ADD if you want to
+# make sure your gcc understands it.
+#
+# The effects of this macro depend on the current language (_AC_LANG).
AC_DEFUN([gl_MANYWARN_ALL_GCC],
+[_AC_LANG_DISPATCH([$0], _AC_LANG, $@)])
+
+# Specialization for _AC_LANG = C.
+# Use of m4_defun rather than AC_DEFUN works around a bug in autoconf < 2.63b.
+m4_defun([gl_MANYWARN_ALL_GCC(C)],
[
- gl_manywarn_set=
- for gl_manywarn_item in \
- -Wall \
- -W \
- -Wformat-y2k \
- -Wformat-nonliteral \
- -Wformat-security \
- -Winit-self \
- -Wmissing-include-dirs \
- -Wswitch-default \
- -Wswitch-enum \
- -Wunused \
- -Wunknown-pragmas \
- -Wstrict-aliasing \
- -Wstrict-overflow \
- -Wsystem-headers \
- -Wfloat-equal \
- -Wtraditional \
- -Wtraditional-conversion \
- -Wdeclaration-after-statement \
- -Wundef \
- -Wshadow \
- -Wunsafe-loop-optimizations \
- -Wpointer-arith \
- -Wbad-function-cast \
- -Wc++-compat \
- -Wcast-qual \
- -Wcast-align \
- -Wwrite-strings \
- -Wconversion \
- -Wsign-conversion \
- -Wlogical-op \
- -Waggregate-return \
- -Wstrict-prototypes \
- -Wold-style-definition \
- -Wmissing-prototypes \
- -Wmissing-declarations \
- -Wmissing-noreturn \
- -Wmissing-format-attribute \
- -Wpacked \
- -Wpadded \
- -Wredundant-decls \
- -Wnested-externs \
- -Wunreachable-code \
- -Winline \
- -Winvalid-pch \
- -Wlong-long \
- -Wvla \
- -Wvolatile-register-var \
- -Wdisabled-optimization \
- -Wstack-protector \
- -Woverlength-strings \
- -Wbuiltin-macro-redefined \
- -Wmudflap \
- -Wpacked-bitfield-compat \
- -Wsync-nand \
- ; do
- gl_manywarn_set="$gl_manywarn_set $gl_manywarn_item"
- done
- # The following are not documented in the manual but are included in
- # output from gcc --help=warnings.
- for gl_manywarn_item in \
- -Wattributes \
- -Wcoverage-mismatch \
- -Wmultichar \
- -Wunused-macros \
- ; do
+ AC_LANG_PUSH([C])
+
+ dnl First, check for some issues that only occur when combining multiple
+ dnl gcc warning categories.
+ AC_REQUIRE([AC_PROG_CC])
+ if test -n "$GCC"; then
+
+ dnl Check if -W -Werror -Wno-missing-field-initializers is supported
+ dnl with the current $CC $CFLAGS $CPPFLAGS.
+ AC_MSG_CHECKING([whether -Wno-missing-field-initializers is supported])
+ AC_CACHE_VAL([gl_cv_cc_nomfi_supported], [
+ gl_save_CFLAGS="$CFLAGS"
+ CFLAGS="$CFLAGS -W -Werror -Wno-missing-field-initializers"
+ AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM([[]], [[]])],
+ [gl_cv_cc_nomfi_supported=yes],
+ [gl_cv_cc_nomfi_supported=no])
+ CFLAGS="$gl_save_CFLAGS"])
+ AC_MSG_RESULT([$gl_cv_cc_nomfi_supported])
+
+ if test "$gl_cv_cc_nomfi_supported" = yes; then
+ dnl Now check whether -Wno-missing-field-initializers is needed
+ dnl for the { 0, } construct.
+ AC_MSG_CHECKING([whether -Wno-missing-field-initializers is needed])
+ AC_CACHE_VAL([gl_cv_cc_nomfi_needed], [
+ gl_save_CFLAGS="$CFLAGS"
+ CFLAGS="$CFLAGS -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_cc_nomfi_needed=no],
+ [gl_cv_cc_nomfi_needed=yes])
+ CFLAGS="$gl_save_CFLAGS"
+ ])
+ AC_MSG_RESULT([$gl_cv_cc_nomfi_needed])
+ fi
+
+ dnl Next, check if -Werror -Wuninitialized is useful with the
+ dnl user's choice of $CFLAGS; some versions of gcc warn that it
+ dnl has no effect if -O is not also used
+ AC_MSG_CHECKING([whether -Wuninitialized is supported])
+ AC_CACHE_VAL([gl_cv_cc_uninitialized_supported], [
+ gl_save_CFLAGS="$CFLAGS"
+ CFLAGS="$CFLAGS -Werror -Wuninitialized"
+ AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM([[]], [[]])],
+ [gl_cv_cc_uninitialized_supported=yes],
+ [gl_cv_cc_uninitialized_supported=no])
+ CFLAGS="$gl_save_CFLAGS"])
+ AC_MSG_RESULT([$gl_cv_cc_uninitialized_supported])
+
+ 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.m4 | sort) \
+ # <(gcc --help=warnings | sed -n 's/^ \(-[^ ]*\) .*/\1/p' | sort |
+ # grep -v -x -F -f <(
+ # awk '/^[^#]/ {print $1}' ../build-aux/gcc-warning.spec))
+
+ gl_manywarn_set=
+ for gl_manywarn_item in -fno-common \
+ -W \
+ -Wabi \
+ -Waddress \
+ -Waggressive-loop-optimizations \
+ -Wall \
+ -Wattributes \
+ -Wbad-function-cast \
+ -Wbool-compare \
+ -Wbool-operation \
+ -Wbuiltin-declaration-mismatch \
+ -Wbuiltin-macro-redefined \
+ -Wcast-align \
+ -Wchar-subscripts \
+ -Wchkp \
+ -Wclobbered \
+ -Wcomment \
+ -Wcomments \
+ -Wcoverage-mismatch \
+ -Wcpp \
+ -Wdangling-else \
+ -Wdate-time \
+ -Wdeprecated \
+ -Wdeprecated-declarations \
+ -Wdesignated-init \
+ -Wdisabled-optimization \
+ -Wdiscarded-array-qualifiers \
+ -Wdiscarded-qualifiers \
+ -Wdiv-by-zero \
+ -Wdouble-promotion \
+ -Wduplicated-branches \
+ -Wduplicated-cond \
+ -Wduplicate-decl-specifier \
+ -Wempty-body \
+ -Wendif-labels \
+ -Wenum-compare \
+ -Wexpansion-to-defined \
+ -Wextra \
+ -Wformat-contains-nul \
+ -Wformat-extra-args \
+ -Wformat-nonliteral \
+ -Wformat-security \
+ -Wformat-signedness \
+ -Wformat-y2k \
+ -Wformat-zero-length \
+ -Wframe-address \
+ -Wfree-nonheap-object \
+ -Whsa \
+ -Wignored-attributes \
+ -Wignored-qualifiers \
+ -Wimplicit \
+ -Wimplicit-function-declaration \
+ -Wimplicit-int \
+ -Wincompatible-pointer-types \
+ -Winit-self \
+ -Winline \
+ -Wint-conversion \
+ -Wint-in-bool-context \
+ -Wint-to-pointer-cast \
+ -Winvalid-memory-model \
+ -Winvalid-pch \
+ -Wjump-misses-init \
+ -Wlogical-not-parentheses \
+ -Wlogical-op \
+ -Wmain \
+ -Wmaybe-uninitialized \
+ -Wmemset-elt-size \
+ -Wmemset-transposed-args \
+ -Wmisleading-indentation \
+ -Wmissing-braces \
+ -Wmissing-declarations \
+ -Wmissing-field-initializers \
+ -Wmissing-include-dirs \
+ -Wmissing-parameter-type \
+ -Wmissing-prototypes \
+ -Wmultichar \
+ -Wnarrowing \
+ -Wnested-externs \
+ -Wnonnull \
+ -Wnonnull-compare \
+ -Wnull-dereference \
+ -Wodr \
+ -Wold-style-declaration \
+ -Wold-style-definition \
+ -Wopenmp-simd \
+ -Woverflow \
+ -Woverlength-strings \
+ -Woverride-init \
+ -Wpacked \
+ -Wpacked-bitfield-compat \
+ -Wparentheses \
+ -Wpointer-arith \
+ -Wpointer-compare \
+ -Wpointer-sign \
+ -Wpointer-to-int-cast \
+ -Wpragmas \
+ -Wpsabi \
+ -Wrestrict \
+ -Wreturn-local-addr \
+ -Wreturn-type \
+ -Wscalar-storage-order \
+ -Wsequence-point \
+ -Wshadow \
+ -Wshift-count-negative \
+ -Wshift-count-overflow \
+ -Wshift-negative-value \
+ -Wsizeof-array-argument \
+ -Wsizeof-pointer-memaccess \
+ -Wstack-protector \
+ -Wstrict-aliasing \
+ -Wstrict-overflow \
+ -Wstrict-prototypes \
+ -Wsuggest-attribute=const \
+ -Wsuggest-attribute=format \
+ -Wsuggest-attribute=noreturn \
+ -Wsuggest-attribute=pure \
+ -Wsuggest-final-methods \
+ -Wsuggest-final-types \
+ -Wswitch \
+ -Wswitch-bool \
+ -Wswitch-default \
+ -Wswitch-unreachable \
+ -Wsync-nand \
+ -Wsystem-headers \
+ -Wtautological-compare \
+ -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 \
+ -Wvarargs \
+ -Wvariadic-macros \
+ -Wvector-operation-performance \
+ -Wvla \
+ -Wvolatile-register-var \
+ -Wwrite-strings \
+ \
+ ; 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.
+ # Would prefer "min (PTRDIFF_MAX, SIZE_MAX)", but it must be a literal.
+ # Also, AC_COMPUTE_INT requires it to fit in a long; it is 2**63 on
+ # the only platforms where it does not fit in a long, so make that
+ # a special case.
+ AC_MSG_CHECKING([max safe object size])
+ AC_COMPUTE_INT([gl_alloc_max],
+ [LONG_MAX < (PTRDIFF_MAX < (size_t) -1 ? PTRDIFF_MAX : (size_t) -1)
+ ? -1
+ : PTRDIFF_MAX < (size_t) -1 ? (long) PTRDIFF_MAX : (long) (size_t) -1],
+ [[#include <limits.h>
+ #include <stddef.h>
+ #include <stdint.h>
+ ]],
+ [gl_alloc_max=2147483647])
+ case $gl_alloc_max in
+ -1) gl_alloc_max=9223372036854775807;;
+ esac
+ AC_MSG_RESULT([$gl_alloc_max])
+ gl_manywarn_set="$gl_manywarn_set -Walloc-size-larger-than=$gl_alloc_max"
+ gl_manywarn_set="$gl_manywarn_set -Warray-bounds=2"
+ gl_manywarn_set="$gl_manywarn_set -Wformat-overflow=2"
+ gl_manywarn_set="$gl_manywarn_set -Wformat-truncation=2"
+ gl_manywarn_set="$gl_manywarn_set -Wimplicit-fallthrough=5"
+ gl_manywarn_set="$gl_manywarn_set -Wnormalized=nfc"
+ gl_manywarn_set="$gl_manywarn_set -Wshift-overflow=2"
+ gl_manywarn_set="$gl_manywarn_set -Wstringop-overflow=2"
+ gl_manywarn_set="$gl_manywarn_set -Wunused-const-variable=2"
+ gl_manywarn_set="$gl_manywarn_set -Wvla-larger-than=4031"
+
+ # These are needed for older GCC versions.
+ if test -n "$GCC"; then
+ case `($CC --version) 2>/dev/null` in
+ 'gcc (GCC) '[[0-3]].* | \
+ 'gcc (GCC) '4.[[0-7]].*)
+ gl_manywarn_set="$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_cc_nomfi_needed" = yes; then
+ gl_manywarn_set="$gl_manywarn_set -Wno-missing-field-initializers"
+ fi
+
+ if test "$gl_cv_cc_uninitialized_supported" = no; then
+ gl_manywarn_set="$gl_manywarn_set -Wno-uninitialized"
+ fi
+
$1=$gl_manywarn_set
+
+ AC_LANG_POP([C])
+])
+
+# Specialization for _AC_LANG = C++.
+# Use of m4_defun rather than AC_DEFUN works around a bug in autoconf < 2.63b.
+m4_defun([gl_MANYWARN_ALL_GCC(C++)],
+[
+ gl_MANYWARN_ALL_GCC_CXX_IMPL([$1])
])