delete trailing whitespace from control files
[debian/gzip] / m4 / manywarnings.m4
index 864fc851982153d719fe4355912335f40dd5d5c8..d831ed2eb60ab537a446c18e20a54a421e4fb015 100644 (file)
@@ -1,5 +1,5 @@
-# manywarnings.m4 serial 4
-dnl Copyright (C) 2008-2012 Free Software Foundation, Inc.
+# manywarnings.m4 serial 17
+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.
@@ -33,151 +33,302 @@ AC_DEFUN([gl_MANYWARN_COMPLEMENT],
 # 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, $@)])
+
+# Specialization for _AC_LANG = C.
+# Use of m4_defun rather than AC_DEFUN works around a bug in autoconf < 2.63b.
+m4_defun([gl_MANYWARN_ALL_GCC(C)],
 [
-  dnl First, check if -Wno-missing-field-initializers is needed.
-  dnl -Wmissing-field-initializers is implied by -W, but that issues
-  dnl warnings with GCC version before 4.7, for the common idiom
-  dnl of initializing types on the stack to zero, using { 0, }
+  AC_LANG_PUSH([C])
+
+  dnl First, check for some issues that only occur when combining multiple
+  dnl gcc warning categories.
   AC_REQUIRE([AC_PROG_CC])
   if test -n "$GCC"; then
 
-    dnl First, check -W -Werror -Wno-missing-field-initializers is supported
+    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([$gl_cv_cc_nomfi_supported])
+    AC_CACHE_CHECK([whether -Wno-missing-field-initializers is supported],
+      [gl_cv_cc_nomfi_supported],
+      [gl_save_CFLAGS="$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"
+      ])
 
     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="$CFLAGS -W -Werror"
-        AC_COMPILE_IFELSE(
-          [AC_LANG_PROGRAM(
-             [[void f (void)
-               {
-                 typedef struct { int a; int b; } s_t;
-                 s_t s1 = { 0, };
-               }
-             ]],
-             [[]])],
-          [gl_cv_cc_nomfi_needed=no],
-          [gl_cv_cc_nomfi_needed=yes])
-        CFLAGS="$gl_save_CFLAGS"
-      ])
-      AC_MSG_RESULT([$gl_cv_cc_nomfi_needed])
+      AC_CACHE_CHECK([whether -Wno-missing-field-initializers is needed],
+        [gl_cv_cc_nomfi_needed],
+        [gl_save_CFLAGS="$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"
+        ])
     fi
+
+    dnl Next, check if -Werror -Wuninitialized is useful with the
+    dnl user's choice of $CFLAGS; some versions of gcc warn that it
+    dnl has no effect if -O is not also used
+    AC_CACHE_CHECK([whether -Wuninitialized is supported],
+      [gl_cv_cc_uninitialized_supported],
+      [gl_save_CFLAGS="$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"
+      ])
+
   fi
 
+  # 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)
+
   gl_manywarn_set=
-  for gl_manywarn_item in \
-    -Wall \
+  for gl_manywarn_item in -fno-common \
     -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 \
+    -Waddress \
+    -Waggressive-loop-optimizations \
+    -Wall \
+    -Wattribute-alias \
+    -Wattributes \
     -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 \
+    -Wbool-compare \
+    -Wbool-operation \
+    -Wbuiltin-declaration-mismatch \
     -Wbuiltin-macro-redefined \
-    -Wmudflap \
-    -Wpacked-bitfield-compat \
-    -Wsync-nand \
-    ; do
-    gl_manywarn_set="$gl_manywarn_set $gl_manywarn_item"
-  done
-  # The following are not documented in the manual but are included in
-  # output from gcc --help=warnings.
-  for gl_manywarn_item in \
-    -Wattributes \
+    -Wcast-align \
+    -Wcast-align=strict \
+    -Wcast-function-type \
+    -Wchar-subscripts \
+    -Wclobbered \
+    -Wcomment \
+    -Wcomments \
     -Wcoverage-mismatch \
-    -Wunused-macros \
-    ; do
-    gl_manywarn_set="$gl_manywarn_set $gl_manywarn_item"
-  done
-  # More warnings from gcc 4.6.2 --help=warnings.
-  for gl_manywarn_item in \
-    -Wabi \
     -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 \
-    -Wformat=2 \
+    -Wframe-address \
+    -Wfree-nonheap-object \
+    -Whsa \
+    -Wif-not-aligned \
+    -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 \
+    -Wlogical-not-parentheses \
+    -Wlogical-op \
+    -Wmain \
+    -Wmaybe-uninitialized \
+    -Wmemset-elt-size \
+    -Wmemset-transposed-args \
+    -Wmisleading-indentation \
+    -Wmissing-attributes \
+    -Wmissing-braces \
+    -Wmissing-declarations \
+    -Wmissing-field-initializers \
+    -Wmissing-include-dirs \
+    -Wmissing-parameter-type \
+    -Wmissing-prototypes \
     -Wmultichar \
-    -Wnormalized=nfc \
+    -Wmultistatement-macros \
+    -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 \
+    -Wpacked-not-aligned \
+    -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-div \
+    -Wsizeof-pointer-memaccess \
+    -Wstack-protector \
+    -Wstrict-aliasing \
+    -Wstrict-overflow \
+    -Wstrict-prototypes \
+    -Wstringop-truncation \
+    -Wsuggest-attribute=cold \
     -Wsuggest-attribute=const \
+    -Wsuggest-attribute=format \
+    -Wsuggest-attribute=malloc \
     -Wsuggest-attribute=noreturn \
     -Wsuggest-attribute=pure \
+    -Wsuggest-final-methods \
+    -Wsuggest-final-types \
+    -Wswitch \
+    -Wswitch-bool \
+    -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
 
-  # Disable the missing-field-initializers warning if needed
+  # 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])
 ])