X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/3eb4f1a3e62807125a815dc572da9204b5b51865..39bace5da815c0290ce5e84628ca7615307b8349:/configure.ac

diff --git a/configure.ac b/configure.ac
index cf42d2c6..992e2033 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,6 +1,6 @@
 # Configure template for GNU Bison.                   -*-Autoconf-*-
 #
-# Copyright (C) 2001-2012 Free Software Foundation, Inc.
+# Copyright (C) 2001-2013 Free Software Foundation, Inc.
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -18,7 +18,7 @@
 # In order for some versions of Sun Studio to compile our C++ test cases
 # correctly, we need Autoconf 2.64 or better to handle the restrict
 # keyword in at least string.h from gnulib.  We need Autoconf 2.68 or
-# better to avoid a typo in the `configure --help' entry for the YACC
+# better to avoid a typo in the 'configure --help' entry for the YACC
 # environment variable.
 AC_PREREQ([2.68])
 m4_pattern_forbid([^gl_[A-Z]])
@@ -26,7 +26,7 @@ m4_pattern_forbid([^gl_[A-Z]])
 AC_INIT([GNU Bison],
         m4_esyscmd([build-aux/git-version-gen .tarball-version]),
         [bug-bison@gnu.org])
-AC_SUBST([PACKAGE_COPYRIGHT_YEAR], [2012])
+AC_SUBST([PACKAGE_COPYRIGHT_YEAR], [2013])
 AC_DEFINE_UNQUOTED([PACKAGE_COPYRIGHT_YEAR], [$PACKAGE_COPYRIGHT_YEAR],
                    [The copyright year for this package])
 
@@ -60,6 +60,20 @@ AC_PROG_CXX
 # Gnulib (early checks).
 gl_EARLY
 
+# Gnulib uses '#pragma GCC diagnostic push' to silence some
+# warnings, but older gcc doesn't support this.
+AC_CACHE_CHECK([whether pragma GCC diagnostic push works],
+  [lv_cv_gcc_pragma_push_works], [
+  save_CFLAGS=$CFLAGS
+  CFLAGS='-Wunknown-pragmas -Werror'
+  AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+    #pragma GCC diagnostic push
+    #pragma GCC diagnostic pop
+  ]])],
+  [lv_cv_gcc_pragma_push_works=yes],
+  [lv_cv_gcc_pragma_push_works=no])
+  CFLAGS=$save_CFLAGS])
+
 AC_ARG_ENABLE([gcc-warnings],
 [  --enable-gcc-warnings   turn on lots of GCC warnings (not recommended)],
 [case $enable_gcc_warnings in
@@ -69,23 +83,53 @@ AC_ARG_ENABLE([gcc-warnings],
               [enable_gcc_warnings=no])
 if test "$enable_gcc_warnings" = yes; then
   warn_common='-Wall -Wextra -Wno-sign-compare -Wcast-align
-    -Wcast-qual -Wformat -Wpointer-arith -Wwrite-strings'
-  warn_c='-Wbad-function-cast -Wmissing-declarations -Wmissing-prototypes
-    -Wshadow -Wstrict-prototypes'
+    -Wformat -Wpointer-arith -Wwrite-strings'
+  warn_c='-Wbad-function-cast -Wshadow -Wstrict-prototypes'
   warn_cxx='-Wnoexcept'
+  # Warnings for the test suite only.
+  #
+  # -fno-color-diagnostics: Clang's use of colors in the error
+  # messages is confusing the tests looking at the compiler's output
+  # (e.g., synclines.at).
+  warn_tests='-Wundef -pedantic -Wsign-compare -fno-color-diagnostics'
 
   AC_LANG_PUSH([C])
+  # Clang supports many of GCC's -W options, but only issues warnings
+  # on the ones it does not recognize.  In that case, gl_WARN_ADD
+  # thinks the option is supported, and unknown options are then added
+  # to CFLAGS.  But then, when -Werror is added in the test suite for
+  # instance, the warning about the unknown option turns into an
+  # error.
+  #
+  # This should be addressed by gnulib's gl_WARN_ADD, but in the
+  # meanwhile, turn warnings about unknown options into errors in
+  # CFLAGS, and restore CFLAGS after the tests.
+  save_CFLAGS=$CFLAGS
+  gl_WARN_ADD([-Werror=unknown-warning-option], [CFLAGS])
   for i in $warn_common $warn_c;
   do
     gl_WARN_ADD([$i], [WARN_CFLAGS])
   done
   gl_WARN_ADD([-Werror], [WERROR_CFLAGS])
+
+  # Warnings for the test suite, and maybe for bison if GCC is modern
+  # enough.
+  gl_WARN_ADD([-Wmissing-declarations], [WARN_CFLAGS_TEST])
+  gl_WARN_ADD([-Wmissing-prototypes], [WARN_CFLAGS_TEST])
+  test $lv_cv_gcc_pragma_push_works = yes &&
+    AS_VAR_APPEND([WARN_CFLAGS], [" $WARN_CFLAGS_TEST"])
+
   # Warnings for the test suite only.
-  gl_WARN_ADD([-Wundef], [WARN_CFLAGS_TEST])
-  gl_WARN_ADD([-pedantic], [WARN_CFLAGS_TEST])
+  for i in $warn_tests;
+  do
+    gl_WARN_ADD([$i], [WARN_CFLAGS_TEST])
+  done
+  CFLAGS=$save_CFLAGS
   AC_LANG_POP([C])
 
   AC_LANG_PUSH([C++])
+  save_CXXFLAGS=$CXXFLAGS
+  gl_WARN_ADD([-Werror=unknown-warning-option], [CXXFLAGS])
   for i in $warn_common $warn_cxx;
   do
     gl_WARN_ADD([$i], [WARN_CXXFLAGS])
@@ -94,13 +138,24 @@ if test "$enable_gcc_warnings" = yes; then
               [AC_LANG_PROGRAM([], [nullptr])])
   gl_WARN_ADD([-Werror], [WERROR_CXXFLAGS])
   # Warnings for the test suite only.
-  gl_WARN_ADD([-Wundef], [WARN_CXXFLAGS_TEST])
-  gl_WARN_ADD([-pedantic], [WARN_CXXFLAGS_TEST])
+  for i in $warn_tests;
+  do
+    gl_WARN_ADD([$i], [WARN_CXXFLAGS_TEST])
+  done
+  # Clang++ 3.2+ reject C code generated by Flex.
+  gl_WARN_ADD([-Wno-null-conversion], [FLEX_SCANNER_CXXFLAGS])
+  # So does G++ 4.8...
+  gl_WARN_ADD([-Wno-sign-compare], [FLEX_SCANNER_CXXFLAGS])
+  # ... possiby in std=c++11 mode.
+  gl_WARN_ADD([-Wno-zero-as-null-pointer-constant], [FLEX_SCANNER_CXXFLAGS])
+  CXXFLAGS=$save_CXXFLAGS
   AC_LANG_POP([C++])
 fi
 
 BISON_TEST_FOR_WORKING_C_COMPILER
+BISON_C_COMPILER_POSIXLY_CORRECT
 BISON_TEST_FOR_WORKING_CXX_COMPILER
+BISON_CXX_COMPILER_POSIXLY_CORRECT
 
 AC_ARG_ENABLE([yacc],
   [AC_HELP_STRING([--disable-yacc],
@@ -118,8 +173,12 @@ AC_SUBST([YACC_SCRIPT])
 AC_SUBST([YACC_LIBRARY])
 
 # Checks for programs.
+AM_MISSING_PROG([DOT], [dot])
 AC_PROG_LEX
-$LEX_IS_FLEX || AC_MSG_ERROR([Flex is required])
+$LEX_IS_FLEX || test "X$LEX" = X: || {
+  AC_MSG_WARN([bypassing lex because flex is required])
+  LEX=:
+}
 AC_PROG_YACC
 AC_PROG_RANLIB
 AC_PROG_GNU_M4
@@ -174,10 +233,16 @@ case $VALGRIND:$host_os in
   '':*) ;;
   *:darwin*)
     # See README-hacking.
-    # VALGRIND+=' --suppressions=$(abs_top_srcdir)/build-aux/darwin11.4.0.valgrind'
+    # VALGRIND+='-q --suppressions=$(abs_top_srcdir)/build-aux/darwin11.4.0.valgrind'
     VALGRIND=;;
   *:*)
-    AC_SUBST([VALGRIND_PREBISON], [$VALGRIND -q]);;
+    suppfile=build-aux/$host_os.valgrind
+    if test -f "$srcdir/$suppfile"; then
+      VALGRIND="$VALGRIND --gen-suppressions=all"
+      VALGRIND="$VALGRIND --suppressions=\$(abs_top_srcdir)/$suppfile"
+    fi
+    AC_SUBST([VALGRIND_PREBISON], ["$VALGRIND -q"])
+    ;;
 esac
 
 AM_MISSING_PROG([AUTOM4TE], [autom4te])
@@ -187,19 +252,6 @@ AC_SUBST([GCC])
 gt_JAVACOMP([1.3], [1.4])
 gt_JAVAEXEC
 
-# We use gnulib, but from lib/local.mk instead of lib/Makefile.am.
-# So prefix paths with lib/.  See also etc/prefix-gnulib-mk.
-gl_LIBOBJS=`echo "$gl_LIBOBJS" | sed -e 's, , lib/,g'`
-# Listing the names of the variables to prefix is error-prone.
-# Rather, adjust all the AC_SUBST variables whose name ends in '_H',
-# and whose content ends in '.h'.
-for ac_var in $ac_subst_vars
-do
-  eval "ac_val=\$$ac_var"
-  case $ac_var=$ac_val in
-    (*_H=*.h) eval "$ac_var=lib/\$$ac_var";;
-  esac
-done
 AC_CONFIG_FILES([Makefile
                  po/Makefile.in
                  doc/yacc.1])