X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Fregex.m4;h=e5468c655b642f762fa1c6865d42456f02cd9288;hb=84b0840f913fdc2d2f9c679decaed57673896592;hp=a9c238356722338c8e5a5aea6213b9fbbc11b552;hpb=1552be320dc029cfecda95ec298ee7f2913e5a7e;p=gnulib.git

diff --git a/m4/regex.m4 b/m4/regex.m4
index a9c238356..e5468c655 100644
--- a/m4/regex.m4
+++ b/m4/regex.m4
@@ -1,15 +1,23 @@
-#serial 1
+#serial 2
 
-dnl From grep.
+dnl Derived from code in GNU grep.
 
 AC_DEFUN(jm_WITH_REGEX,
   [
-    AC_ARG_WITH(included-regex,
-		[  --without-included-regex don't compile regex],
-		jm_with_regex=$withval,
-		jm_with_regex=yes)
-    if test "$jm_with_regex" = yes; then
-      LIBOBJS="$LIBOBJS regex.o"
-    fi
+    dnl Even packages that don't use regex.c can use this macro.
+    dnl Of course, for them it doesn't do anything.
+
+    syscmd([test -f lib/regex.c])
+    ifelse(sysval, 0,
+      [
+	AC_ARG_WITH(included-regex,
+	    [  --without-included-regex don't compile regex (use with caution)],
+		    jm_with_regex=$withval,
+		    jm_with_regex=yes)
+	if test "$jm_with_regex" = yes; then
+	  LIBOBJS="$LIBOBJS regex.o"
+	fi
+      ],
+    )
   ]
 )