cpphash.c (funlike_macroexpand): Make sure not to walk p1 past l1 when deleting…

cpphash.c (funlike_macroexpand): Make sure not to walk p1 past l1 when deleting whitespace and markers.

	* cpphash.c (funlike_macroexpand): Make sure not to walk p1
	past l1 when deleting whitespace and markers.

From-SVN: r34027

gcc/ChangeLog

 2000-05-19  Zack Weinberg  <zack@wolery.cumb.org>
 
+	* cpphash.c (funlike_macroexpand): Make sure not to walk p1
+	past l1 when deleting whitespace and markers.              
+
 	* cpplex.c (_cpp_scan_until): Clear AUX field of tokens.
 	* cpplib.c (do_unassert): Put the list to compare against on
 	the stack.

gcc/cpphash.c

@@ -1578,7 +1578,7 @@ funlike_macroexpand (pfile, hp, args)
 	    {
 	      /* Arg is concatenated before: delete leading whitespace,
 		 whitespace markers, and no-reexpansion markers.  */
-	      while (p1 != l1)
+	      while (p1 < l1)
 		{
 		  if (is_space(p1[0]))
 		    p1++;
@@ -1592,7 +1592,7 @@ funlike_macroexpand (pfile, hp, args)
 	    {
 	      /* Arg is concatenated after: delete trailing whitespace,
 		 whitespace markers, and no-reexpansion markers.  */
-	      while (p1 != l1)
+	      while (p1 < l1)
 		{
 		  if (is_space(l1[-1]))
 		    l1--;
@@ -1612,7 +1612,7 @@ funlike_macroexpand (pfile, hp, args)
 
 	  /* Delete any no-reexpansion marker that precedes
 	     an identifier at the beginning of the argument. */
-	  if (p1[0] == '\r' && p1[1] == '-')
+	  if (p1 + 2 <= l1 && p1[0] == '\r' && p1[1] == '-')
 	    p1 += 2;
 
 	  memcpy (xbuf + totlen, p1, l1 - p1);

gcc/testsuite/gcc.dg/20000519-1.c

+/* Regression test for preprocessor crash.
+   Reported by Mathias Froehlich <frohlich@na.uni-tuebingen.de>.  */
+/* { dg-do preprocess } */
+#define foo
+
+#define __CAT__(a,b,c,d) a##b##c##d
+#define CAT(a,b,c,d) __CAT__(a,b,c,d)
+
+#define bar CAT(,foo,bar,)
+bar