m4: use a safer pattern to enable/disable output

[bison.git] / configure.ac

diff --git a/configure.ac b/configure.ac
index 9395568563a7be292a909667b978b61747f46db8..83e20acb01ade45da8f32b2fd046315dd6bd1a16 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -70,8 +70,20 @@ if test "$enable_gcc_warnings" = yes; then
     -Wcast-qual -Wformat -Wpointer-arith -Wwrite-strings'
   warn_c='-Wbad-function-cast -Wmissing-declarations -Wmissing-prototypes
     -Wshadow -Wstrict-prototypes'
     -Wcast-qual -Wformat -Wpointer-arith -Wwrite-strings'
   warn_c='-Wbad-function-cast -Wmissing-declarations -Wmissing-prototypes
     -Wshadow -Wstrict-prototypes'

-  warn_cxx='-Wnoexcept -Wzero-as-null-pointer-constant'
+  warn_cxx='-Wnoexcept'

   AC_LANG_PUSH([C])
   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])
   for i in $warn_common $warn_c;
   do
     gl_WARN_ADD([$i], [WARN_CFLAGS])


@@ -80,22 +92,29 @@ if test "$enable_gcc_warnings" = yes; then
   # Warnings for the test suite only.
   gl_WARN_ADD([-Wundef], [WARN_CFLAGS_TEST])
   gl_WARN_ADD([-pedantic], [WARN_CFLAGS_TEST])
   # Warnings for the test suite only.
   gl_WARN_ADD([-Wundef], [WARN_CFLAGS_TEST])
   gl_WARN_ADD([-pedantic], [WARN_CFLAGS_TEST])

+  CFLAGS=$save_CFLAGS

   AC_LANG_POP([C])
 
   AC_LANG_PUSH([C++])
   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])
   done
   for i in $warn_common $warn_cxx;
   do
     gl_WARN_ADD([$i], [WARN_CXXFLAGS])
   done

+  gl_WARN_ADD([-Wzero-as-null-pointer-constant], [WARN_CXXFLAGS],
+              [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])
   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])

+  CXXFLAGS=$save_CXXFLAGS

   AC_LANG_POP([C++])
 fi
 
 BISON_TEST_FOR_WORKING_C_COMPILER
 BISON_TEST_FOR_WORKING_CXX_COMPILER
   AC_LANG_POP([C++])
 fi
 
 BISON_TEST_FOR_WORKING_C_COMPILER
 BISON_TEST_FOR_WORKING_CXX_COMPILER

+BISON_C_COMPILER_POSIXLY_CORRECT

 
 AC_ARG_ENABLE([yacc],
   [AC_HELP_STRING([--disable-yacc],
 
 AC_ARG_ENABLE([yacc],
   [AC_HELP_STRING([--disable-yacc],


@@ -113,6 +132,7 @@ AC_SUBST([YACC_SCRIPT])
 AC_SUBST([YACC_LIBRARY])
 
 # Checks for programs.
 AC_SUBST([YACC_LIBRARY])
 
 # Checks for programs.

+AM_MISSING_PROG([DOT], [dot])

 AC_PROG_LEX
 $LEX_IS_FLEX || AC_MSG_ERROR([Flex is required])
 AC_PROG_YACC
 AC_PROG_LEX
 $LEX_IS_FLEX || AC_MSG_ERROR([Flex is required])
 AC_PROG_YACC


@@ -121,6 +141,10 @@ AC_PROG_GNU_M4
 AC_DEFINE_UNQUOTED([M4], ["$M4"], [Define to the GNU M4 executable name.])
 AC_DEFINE_UNQUOTED([M4_GNU_OPTION], ["$M4_GNU"], [Define to "-g" if GNU M4
 supports -g, otherwise to "".])
 AC_DEFINE_UNQUOTED([M4], ["$M4"], [Define to the GNU M4 executable name.])
 AC_DEFINE_UNQUOTED([M4_GNU_OPTION], ["$M4_GNU"], [Define to "-g" if GNU M4
 supports -g, otherwise to "".])

+AC_PATH_PROG([PERL], [perl])
+if test -z "$PERL"; then
+   AC_MSG_ERROR([perl not found])
+fi

 AM_MISSING_PROG([HELP2MAN], [help2man])
 AC_PATH_PROG([XSLTPROC], [xsltproc])
 AC_SUBST([XSLTPROC])
 AM_MISSING_PROG([HELP2MAN], [help2man])
 AC_PATH_PROG([XSLTPROC], [xsltproc])
 AC_SUBST([XSLTPROC])


@@ -161,6 +185,16 @@ AC_CONFIG_TESTDIR(tests)
 AC_CONFIG_FILES([tests/Makefile tests/atlocal])
 AC_CONFIG_FILES([tests/bison], [chmod +x tests/bison])
 AC_CHECK_PROGS([VALGRIND], [valgrind])
 AC_CONFIG_FILES([tests/Makefile tests/atlocal])
 AC_CONFIG_FILES([tests/bison], [chmod +x tests/bison])
 AC_CHECK_PROGS([VALGRIND], [valgrind])

+case $VALGRIND:$host_os in
+  '':*) ;;
+  *:darwin*)
+    # See README-hacking.
+    # VALGRIND+=' --suppressions=$(abs_top_srcdir)/build-aux/darwin11.4.0.valgrind'
+    VALGRIND=;;
+  *:*)
+    AC_SUBST([VALGRIND_PREBISON], ["$VALGRIND -q"]);;
+esac
+

 AM_MISSING_PROG([AUTOM4TE], [autom4te])
 # Needed by tests/atlocal.in.
 AC_SUBST([GCC])
 AM_MISSING_PROG([AUTOM4TE], [autom4te])
 # Needed by tests/atlocal.in.
 AC_SUBST([GCC])