X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/bcbbf654863dd285b176a0f54a75a28c4bdac1d3..41a4806a825bebfa73a5a9337672735ba1f753c6:/configure.ac

diff --git a/configure.ac b/configure.ac
index 2773167a..651fa139 100644
--- a/configure.ac
+++ b/configure.ac
@@ -72,6 +72,18 @@ if test "$enable_gcc_warnings" = yes; then
     -Wshadow -Wstrict-prototypes'
   warn_cxx='-Wnoexcept'
   AC_LANG_PUSH([C])
+  # Clang supports many of GCC's -W options, but only issues warnings
+  # on the ones it does not recognize.  In that case, gl_WARN_ADD
+  # thinks the option is supported, and unknown options are then added
+  # to CFLAGS.  But then, when -Werror is added in the test suite for
+  # instance, the warning about the unknown option turns into an
+  # error.
+  #
+  # This should be addressed by gnulib's gl_WARN_ADD, but in the
+  # meanwhile, turn warnings about unknown options into errors in
+  # CFLAGS, and restore CFLAGS after the tests.
+  save_CFLAGS=$CFLAGS
+  gl_WARN_ADD([-Werror=unknown-warning-option], [CFLAGS])
   for i in $warn_common $warn_c;
   do
     gl_WARN_ADD([$i], [WARN_CFLAGS])
@@ -80,19 +92,23 @@ if test "$enable_gcc_warnings" = yes; then
   # Warnings for the test suite only.
   gl_WARN_ADD([-Wundef], [WARN_CFLAGS_TEST])
   gl_WARN_ADD([-pedantic], [WARN_CFLAGS_TEST])
+  CFLAGS=$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])
   done
-  gl_WARN_ADD([ -Wzero-as-null-pointer-constant], [WARN_CXXFLAGS],
+  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])
+  CXXFLAGS=$save_CXXFLAGS
   AC_LANG_POP([C++])
 fi
 
@@ -123,6 +139,10 @@ 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_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])
@@ -170,7 +190,7 @@ case $VALGRIND:$host_os in
     # VALGRIND+=' --suppressions=$(abs_top_srcdir)/build-aux/darwin11.4.0.valgrind'
     VALGRIND=;;
   *:*)
-    AC_SUBST([VALGRIND_PREBISON], [$VALGRIND -q]);;
+    AC_SUBST([VALGRIND_PREBISON], ["$VALGRIND -q"]);;
 esac
 
 AM_MISSING_PROG([AUTOM4TE], [autom4te])