summaryrefslogtreecommitdiffstats
path: root/gl/m4/manywarnings.m4
diff options
context:
space:
mode:
Diffstat (limited to 'gl/m4/manywarnings.m4')
-rw-r--r--gl/m4/manywarnings.m4206
1 files changed, 206 insertions, 0 deletions
diff --git a/gl/m4/manywarnings.m4 b/gl/m4/manywarnings.m4
new file mode 100644
index 0000000..a06f26f
--- /dev/null
+++ b/gl/m4/manywarnings.m4
@@ -0,0 +1,206 @@
+# manywarnings.m4 serial 24
+dnl Copyright (C) 2008-2023 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.
+
+dnl From Simon Josefsson
+
+AC_PREREQ([2.64])
+
+# gl_MANYWARN_COMPLEMENT(OUTVAR, LISTVAR, REMOVEVAR)
+# --------------------------------------------------
+# Copy LISTVAR to OUTVAR except for the entries in REMOVEVAR.
+# Elements separated by whitespace. In set logic terms, the function
+# does OUTVAR = LISTVAR \ REMOVEVAR.
+AC_DEFUN([gl_MANYWARN_COMPLEMENT],
+[
+ gl_warn_set=
+ set x $2; shift
+ for gl_warn_item
+ do
+ case " $3 " in
+ *" $gl_warn_item "*)
+ ;;
+ *)
+ AS_VAR_APPEND([gl_warn_set], [" $gl_warn_item"])
+ ;;
+ esac
+ done
+ $1=$gl_warn_set
+])
+
+# gl_MANYWARN_ALL_GCC(VARIABLE)
+# -----------------------------
+# 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, $@)])
+
+# Specialization for _AC_LANG = C.
+AC_DEFUN([gl_MANYWARN_ALL_GCC(C)],
+[
+ AC_LANG_PUSH([C])
+
+ dnl First, check for some issues that only occur when combining multiple
+ dnl gcc warning categories.
+ AC_REQUIRE([AC_PROG_CC])
+ AS_IF([test -n "$GCC"], [
+ AC_CACHE_CHECK([whether -Wno-missing-field-initializers is needed],
+ [gl_cv_cc_nomfi_needed],
+ [gl_cv_cc_nomfi_needed=no
+ gl_save_CFLAGS="$CFLAGS"
+ CFLAGS="$CFLAGS -Wextra -Werror"
+ AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[struct file_data { int desc, name; };
+ struct cmp { struct file_data file[1]; };
+ void f (struct cmp *r)
+ {
+ typedef struct { int a; int b; } s_t;
+ s_t s1 = { 0, };
+ struct cmp cmp = { .file[0].desc = r->file[0].desc + s1.a };
+ *r = cmp;
+ }
+ ]],
+ [[]])],
+ [],
+ [CFLAGS="$CFLAGS -Wno-missing-field-initializers"
+ AC_COMPILE_IFELSE([],
+ [gl_cv_cc_nomfi_needed=yes])])
+ CFLAGS="$gl_save_CFLAGS"
+ ])
+
+ dnl Next, check if -Werror -Wuninitialized is useful with the
+ dnl user's choice of $CFLAGS; some versions of gcc warn that it
+ dnl has no effect if -O is not also used
+ AC_CACHE_CHECK([whether -Wuninitialized is supported],
+ [gl_cv_cc_uninitialized_supported],
+ [gl_save_CFLAGS="$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"
+ ])
+ ])
+
+ # List all gcc warning categories.
+ # To compare this list to your installed GCC's, run this Bash command:
+ #
+ # comm -3 \
+ # <((sed -n 's/^ *\(-[^ 0-9][^ ]*\).*/\1/p' manywarnings.m4; \
+ # awk '/^[^#]/ {print $1}' ../build-aux/gcc-warning.spec) | sort) \
+ # <(LC_ALL=C gcc --help=warnings | sed -n 's/^ \(-[^ ]*\) .*/\1/p' | sort)
+
+ $1=
+ for gl_manywarn_item in -fanalyzer -fstrict-flex-arrays \
+ -Wall \
+ -Warith-conversion \
+ -Wbad-function-cast \
+ -Wcast-align=strict \
+ -Wdate-time \
+ -Wdisabled-optimization \
+ -Wdouble-promotion \
+ -Wduplicated-branches \
+ -Wduplicated-cond \
+ -Wextra \
+ -Wformat-signedness \
+ -Winit-self \
+ -Winline \
+ -Winvalid-pch \
+ -Wlogical-op \
+ -Wmissing-declarations \
+ -Wmissing-include-dirs \
+ -Wmissing-prototypes \
+ -Wnested-externs \
+ -Wnull-dereference \
+ -Wold-style-definition \
+ -Wopenmp-simd \
+ -Woverlength-strings \
+ -Wpacked \
+ -Wpointer-arith \
+ -Wshadow \
+ -Wstack-protector \
+ -Wstrict-flex-arrays \
+ -Wstrict-overflow \
+ -Wstrict-prototypes \
+ -Wsuggest-attribute=cold \
+ -Wsuggest-attribute=const \
+ -Wsuggest-attribute=format \
+ -Wsuggest-attribute=malloc \
+ -Wsuggest-attribute=noreturn \
+ -Wsuggest-attribute=pure \
+ -Wsuggest-final-methods \
+ -Wsuggest-final-types \
+ -Wsync-nand \
+ -Wsystem-headers \
+ -Wtrampolines \
+ -Wuninitialized \
+ -Wunknown-pragmas \
+ -Wunsafe-loop-optimizations \
+ -Wunused-macros \
+ -Wvariadic-macros \
+ -Wvector-operation-performance \
+ -Wvla \
+ -Wwrite-strings \
+ \
+ ; do
+ AS_VAR_APPEND([$1], [" $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.
+ AS_VAR_APPEND([$1], [' -Warray-bounds=2'])
+ AS_VAR_APPEND([$1], [' -Wattribute-alias=2'])
+ AS_VAR_APPEND([$1], [' -Wbidi-chars=any,ucn'])
+ AS_VAR_APPEND([$1], [' -Wformat-overflow=2'])
+ AS_VAR_APPEND([$1], [' -Wformat=2'])
+ AS_VAR_APPEND([$1], [' -Wformat-truncation=2'])
+ AS_VAR_APPEND([$1], [' -Wimplicit-fallthrough=5'])
+ AS_VAR_APPEND([$1], [' -Wshift-overflow=2'])
+ AS_VAR_APPEND([$1], [' -Wuse-after-free=3'])
+ AS_VAR_APPEND([$1], [' -Wunused-const-variable=2'])
+ AS_VAR_APPEND([$1], [' -Wvla-larger-than=4031'])
+
+ # These are needed for older GCC versions.
+ if test -n "$GCC" && gl_gcc_version=`($CC --version) 2>/dev/null`; then
+ case $gl_gcc_version in
+ 'gcc (GCC) '[[0-3]].* | \
+ 'gcc (GCC) '4.[[0-7]].*)
+ AS_VAR_APPEND([$1], [' -fdiagnostics-show-option'])
+ AS_VAR_APPEND([$1], [' -funit-at-a-time'])
+ ;;
+ esac
+ case $gl_gcc_version in
+ 'gcc (GCC) '[[0-9]].*)
+ AS_VAR_APPEND([$1], [' -fno-common'])
+ ;;
+ esac
+ fi
+
+ # Disable specific options as needed.
+ if test "$gl_cv_cc_nomfi_needed" = yes; then
+ AS_VAR_APPEND([$1], [' -Wno-missing-field-initializers'])
+ fi
+
+ if test "$gl_cv_cc_uninitialized_supported" = no; then
+ AS_VAR_APPEND([$1], [' -Wno-uninitialized'])
+ fi
+
+ # This warning have too many false alarms in GCC 11.2.1.
+ # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101713
+ AS_VAR_APPEND([$1], [' -Wno-analyzer-malloc-leak'])
+
+ AC_LANG_POP([C])
+])
+
+# Specialization for _AC_LANG = C++.
+AC_DEFUN([gl_MANYWARN_ALL_GCC(C++)],
+[
+ gl_MANYWARN_ALL_GCC_CXX_IMPL([$1])
+])