test "x$NON_GCC_TEST_OPTIONS" != x && CC="$CC $NON_GCC_TEST_OPTIONS"
fi
-### Use -Wdeclaration-after-statement if the compiler supports it
-AC_MSG_CHECKING([whether gcc understands -Wdeclaration-after-statement])
-SAVE_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -Wdeclaration-after-statement"
-AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[]])], has_option=yes, has_option=no)
-if test $has_option = yes; then
- C_WARNINGS_SWITCH="-Wdeclaration-after-statement $C_WARNINGS_SWITCH"
-fi
-AC_MSG_RESULT($has_option)
-CFLAGS="$SAVE_CFLAGS"
-unset has_option
-unset SAVE_CFLAGS
-
-### Use -Wold-style-definition if the compiler supports it
-# This can be removed when conversion to standard C is finished.
-AC_MSG_CHECKING([whether gcc understands -Wold-style-definition])
-SAVE_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -Wold-style-definition"
-AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[]])], has_option=yes, has_option=no)
-if test $has_option = yes; then
- C_WARNINGS_SWITCH="-Wold-style-definition $C_WARNINGS_SWITCH"
-fi
-AC_MSG_RESULT($has_option)
-CFLAGS="$SAVE_CFLAGS"
-unset has_option
-unset SAVE_CFLAGS
-
-### Use -Wimplicit-function-declaration if the compiler supports it
-AC_MSG_CHECKING([whether gcc understands -Wimplicit-function-declaration])
-SAVE_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -Wimplicit-function-declaration"
-AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[]])], has_option=yes, has_option=no)
-if test $has_option = yes; then
- C_WARNINGS_SWITCH="-Wimplicit-function-declaration $C_WARNINGS_SWITCH"
-fi
-AC_MSG_RESULT($has_option)
-CFLAGS="$SAVE_CFLAGS"
-unset has_option
-unset SAVE_CFLAGS
-
-AC_SUBST(C_WARNINGS_SWITCH)
+AC_ARG_ENABLE([gcc-warnings],
+ [AS_HELP_STRING([--enable-gcc-warnings],
+ [turn on lots of GCC warnings (for developers)])],
+ [case $enableval in
+ yes|no) ;;
+ *) AC_MSG_ERROR([bad value $enableval for gcc-warnings option]) ;;
+ esac
+ gl_gcc_warnings=$enableval],
+ [gl_gcc_warnings=no]
+)
+
+# gl_GCC_VERSION_IFELSE([major], [minor], [run-if-found], [run-if-not-found])
+# ------------------------------------------------
+# If $CPP is gcc-MAJOR.MINOR or newer, then run RUN-IF-FOUND.
+# Otherwise, run RUN-IF-NOT-FOUND.
+AC_DEFUN([gl_GCC_VERSION_IFELSE],
+ [AC_PREPROC_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[
+#if ($1) < __GNUC__ || (($1) == __GNUC__ && ($2) <= __GNUC_MINOR__)
+/* ok */
+#else
+# error "your version of gcc is older than $1.$2"
+#endif
+ ]]),
+ ], [$3], [$4])
+ ]
+)
+
+# When compiling with GCC, prefer -isystem to -I when including system
+# include files, to avoid generating useless diagnostics for the files.
+if test "$gl_gcc_warnings" != yes; then
+ isystem='-I'
+else
+ isystem='-isystem '
+
+ # This, $nw, is the list of warnings we disable.
+ nw=
+
+ case $with_x_toolkit in
+ lucid | athena | motif)
+ # Old toolkits mishandle 'const'.
+ nw="$nw -Wwrite-strings"
+ ;;
+ *)
+ gl_WARN_ADD([-Werror], [WERROR_CFLAGS])
+ ;;
+ esac
+ AC_SUBST([WERROR_CFLAGS])
+
+ nw="$nw -Waggregate-return" # anachronistic
+ nw="$nw -Wlong-long" # C90 is anachronistic (lib/gethrxtime.h)
+ nw="$nw -Wc++-compat" # We don't care about C++ compilers
+ nw="$nw -Wundef" # Warns on '#if GNULIB_FOO' etc in gnulib
+ nw="$nw -Wtraditional" # Warns on #elif which we use often
+ nw="$nw -Wcast-qual" # Too many warnings for now
+ nw="$nw -Wconversion" # Too many warnings for now
+ nw="$nw -Wsystem-headers" # Don't let system headers trigger warnings
+ nw="$nw -Wsign-conversion" # Too many warnings for now
+ nw="$nw -Woverlength-strings" # Not a problem these days
+ nw="$nw -Wtraditional-conversion" # Too many warnings for now
+ nw="$nw -Wpadded" # Our structs are not padded
+ nw="$nw -Wredundant-decls" # We regularly (re)declare getenv etc.
+ nw="$nw -Wlogical-op" # any use of fwrite provokes this
+ nw="$nw -Wformat-nonliteral" # Emacs does this a lot
+ nw="$nw -Wvla" # warnings in gettext.h
+ nw="$nw -Wnested-externs" # use of XARGMATCH/verify_function__
+ nw="$nw -Wswitch-enum" # Too many warnings for now
+ nw="$nw -Wswitch-default" # Too many warnings for now
+ nw="$nw -Wfloat-equal" # e.g., ftoastr.c
+ nw="$nw -Winline" # e.g., dispnew.c's inlining of row_equal_p
+
+ # Emacs doesn't care about shadowing; see
+ # <http://lists.gnu.org/archive/html/emacs-diffs/2011-11/msg00265.html>.
+ nw="$nw -Wshadow"
+
+ # The following lines should be removable at some point.
+ nw="$nw -Wsuggest-attribute=const"
+ nw="$nw -Wsuggest-attribute=pure"
+
+ gl_MANYWARN_ALL_GCC([ws])
+ gl_MANYWARN_COMPLEMENT([ws], [$ws], [$nw])
+ for w in $ws; do
+ gl_WARN_ADD([$w])
+ done
+ gl_WARN_ADD([-Wno-missing-field-initializers]) # We need this one
+ gl_WARN_ADD([-Wno-sign-compare]) # Too many warnings for now
+ gl_WARN_ADD([-Wno-type-limits]) # Too many warnings for now
+ gl_WARN_ADD([-Wno-switch]) # Too many warnings for now
+ gl_WARN_ADD([-Wno-unused-parameter]) # Too many warnings for now
+ gl_WARN_ADD([-Wno-format-nonliteral])
+
+ # In spite of excluding -Wlogical-op above, it is enabled, as of
+ # gcc 4.5.0 20090517.
+ gl_WARN_ADD([-Wno-logical-op])
+
+ gl_WARN_ADD([-fdiagnostics-show-option])
+ gl_WARN_ADD([-funit-at-a-time])
+
+ AC_SUBST([WARN_CFLAGS])
+
+ AC_DEFINE([lint], [1], [Define to 1 if the compiler is checking for lint.])
+ AC_DEFINE([_FORTIFY_SOURCE], [2],
+ [enable compile-time and run-time bounds-checking, and some warnings])
+ AC_DEFINE([GNULIB_PORTCHECK], [1], [enable some gnulib portability checks])
+
+ # We use a slightly smaller set of warning options for lib/.
+ # Remove the following and save the result in GNULIB_WARN_CFLAGS.
+ nw=
+ nw="$nw -Wunused-macros"
+
+ gl_MANYWARN_COMPLEMENT([GNULIB_WARN_CFLAGS], [$WARN_CFLAGS], [$nw])
+ AC_SUBST([GNULIB_WARN_CFLAGS])
+fi
+
#### Some other nice autoconf tests.
if $PKG_CONFIG --exists "$2" 2>&AS_MESSAGE_LOG_FD &&
$1_CFLAGS=`$PKG_CONFIG --cflags "$2" 2>&AS_MESSAGE_LOG_FD` &&
$1_LIBS=`$PKG_CONFIG --libs "$2" 2>&AS_MESSAGE_LOG_FD`; then
-
- $1_CFLAGS=`AS_ECHO(["$$1_CFLAGS"]) | sed -e 's,///*,/,g'`
+ edit_cflags="
+ s,///*,/,g
+ s/^/ /
+ s/ -I/ $isystem/g
+ s/^ //
+ "
+ $1_CFLAGS=`AS_ECHO(["$$1_CFLAGS"]) | sed -e "$edit_cflags"`
$1_LIBS=`AS_ECHO(["$$1_LIBS"]) | sed -e 's,///*,/,g'`
AC_MSG_RESULT([yes CFLAGS='$$1_CFLAGS' LIBS='$$1_LIBS'])
succeeded=yes
AC_SUBST(LD_SWITCH_X_SITE_AUX_RPATH)
if test "${x_includes}" != NONE && test -n "${x_includes}"; then
- C_SWITCH_X_SITE=-I`echo ${x_includes} | sed -e "s/:/ -I/g"`
+ C_SWITCH_X_SITE="$isystem"`echo ${x_includes} | sed -e "s/:/ $isystem/g"`
fi
if test x"${x_includes}" = x; then
HCoop / bpt / emacs.git / blobdiff