diff options
Diffstat (limited to 'configure.ac')
| -rw-r--r-- | configure.ac | 150 |
1 files changed, 149 insertions, 1 deletions
diff --git a/configure.ac b/configure.ac index 32ce4a0..7213159 100644 --- a/configure.ac +++ b/configure.ac @@ -18,10 +18,30 @@ AC_SUBST(SED_FEATURE_VERSION) COPYRIGHT_YEAR=2014 AC_SUBST(COPYRIGHT_YEAR) -AC_PROG_CC +AC_PROG_CC_STDC +AM_PROG_CC_C_O gl_EARLY gl_INIT gl_DISABLE_THREADS + +# 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]) + ] +) + AC_CACHE_CHECK([whether "rt" can be used with fopen], [sed_cv_fopen_rt], [ AC_TRY_RUN([ #include <stdio.h> @@ -185,6 +205,134 @@ case $host in esac AC_SUBST([XFAIL_TESTS]) +AC_ARG_ENABLE([gcc-warnings], + [AS_HELP_STRING([--enable-gcc-warnings], + [turn on many GCC warnings (for developers; best with GNU make)])], + [case $enableval in + yes|no) ;; + *) AC_MSG_ERROR([bad value $enableval for gcc-warnings option]) ;; + esac + gl_gcc_warnings=$enableval], + [ + # GCC provides fine-grained control over diagnostics which + # is used in gnulib for example to suppress warnings from + # certain sections of code. So if this is available and + # we're running from a git repo, then auto enable the warnings. + gl_gcc_warnings=no + gl_GCC_VERSION_IFELSE([4], [6], + [test -d "$srcdir"/.git \ + && ! test -f "$srcdir"/.tarball-version \ + && gl_gcc_warnings=yes])] +) + +if test "$gl_gcc_warnings" = yes; then + gl_WARN_ADD([-Werror], [WERROR_CFLAGS]) + AC_SUBST([WERROR_CFLAGS]) + + nw= + # This, $nw, is the list of warnings we disable. + nw="$nw -Wdeclaration-after-statement" # too useful to forbid + 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 -Wtraditional-conversion" # Too many warnings for now + nw="$nw -Wunreachable-code" # Too many warnings for now + nw="$nw -Wpadded" # Our structs are not padded + nw="$nw -Wredundant-decls" # openat.h declares e.g., mkdirat + nw="$nw -Wlogical-op" # Too many warnings until GCC 4.8.0 + nw="$nw -Wformat-nonliteral" # who.c and pinky.c strftime uses + nw="$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 -Wstack-protector" # not worth working around + # things I might fix soon: + nw="$nw -Wfloat-equal" # sort.c, seq.c + nw="$nw -Wmissing-format-attribute" # copy.c + nw="$nw -Wunsafe-loop-optimizations" # a few src/*.c + nw="$nw -Winline" # system.h's readdir_ignoring_dot_and_dotdot + nw="$nw -Wsuggest-attribute=format" # warns about copy.c and factor.c + + # Using -Wstrict-overflow is a pain, but the alternative is worse. + # For an example, see the code that provoked this report: + # http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33498 + # Code like that still infloops with gcc-4.6.0 and -O2. Scary indeed. + + gl_MANYWARN_ALL_GCC([ws]) + gl_MANYWARN_COMPLEMENT([ws], [$ws], [$nw]) + for w in $ws; do + gl_WARN_ADD([$w]) + done + gl_WARN_ADD([-Wno-sign-compare]) # Too many warnings for now + gl_WARN_ADD([-Wno-unused-parameter]) # Too many warnings for now + gl_WARN_ADD([-Wno-format-nonliteral]) + + # Enable this warning only with gcc-4.8 and newer. Before that + # bounds checking as done in truncate.c was incorrectly flagged. + # See: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43772 + gl_GCC_VERSION_IFELSE([4], [8], [gl_WARN_ADD([-Wlogical-op])]) + + # clang is unduly picky about some things. + AC_CACHE_CHECK([whether the compiler is clang], [utils_cv_clang], + [AC_COMPILE_IFELSE( + [AC_LANG_PROGRAM([[ + #ifndef __clang__ + #error "not clang" + #endif + ]])], + [utils_cv_clang=yes], + [utils_cv_clang=no])]) + if test $utils_cv_clang = yes; then + gl_WARN_ADD([-Wno-format-extra-args]) + gl_WARN_ADD([-Wno-tautological-constant-out-of-range-compare]) + fi + + gl_WARN_ADD([-fdiagnostics-show-option]) + gl_WARN_ADD([-funit-at-a-time]) + + AC_SUBST([WARN_CFLAGS]) + + AC_DEFINE([lint], [1], [Define to 1 if the compiler is checking for lint.]) + AH_VERBATIM([FORTIFY_SOURCE], + [/* Enable compile-time and run-time bounds-checking, and some warnings, + without upsetting glibc 2.15+. */ + #if !defined _FORTIFY_SOURCE && defined __OPTIMIZE__ && __OPTIMIZE__ + # define _FORTIFY_SOURCE 2 + #endif + ]) + AC_DEFINE([GNULIB_PORTCHECK], [1], [enable some gnulib portability checks]) + + # We use a slightly smaller set of warning options for lib/. + # Remove the following and save the result in GNULIB_WARN_CFLAGS. + nw= + nw="$nw -Wstrict-overflow" + nw="$nw -Wuninitialized" + nw="$nw -Wunused-macros" + nw="$nw -Wmissing-prototypes" + nw="$nw -Wold-style-definition" + # FIXME: it may be easy to remove this, since it affects only one file: + # the snprintf call at ftoastr.c:132. + nw="$nw -Wdouble-promotion" + gl_MANYWARN_COMPLEMENT([GNULIB_WARN_CFLAGS], [$WARN_CFLAGS], [$nw]) + AC_SUBST([GNULIB_WARN_CFLAGS]) + + # For gnulib-tests, the set is slightly smaller still. + nw= + nw="$nw -Wstrict-prototypes" + # It's not worth being this picky about test programs. + nw="$nw -Wsuggest-attribute=const" + nw="$nw -Wsuggest-attribute=pure" + gl_MANYWARN_COMPLEMENT([GNULIB_TEST_WARN_CFLAGS], + [$GNULIB_WARN_CFLAGS], [$nw]) + AC_SUBST([GNULIB_TEST_WARN_CFLAGS]) +fi + AC_CONFIG_FILES([testsuite/version.good:testsuite/version.gin]) AC_CONFIG_FILES([ Makefile |