re PR c++/37217 (-Wconversion causes ICE with __builtin_strcmp with one char compare)

2008-08-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>

	PR 37217
	* c-common.c (conversion_warning): Check for null operands.
testsuite/
	* gcc.dg/pr37217.c: New.

From-SVN: r139682

gcc/ChangeLog

 2008-08-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
 
+	PR 37217
+	* c-common.c (convesion_warning): Check for null operands.
+
+2008-08-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
+
 	PR c/31673
 	* c-decl.c (check_for_loop_decls): Improve error message. Give
 	hint.

gcc/c-common.c

@@ -1568,7 +1568,7 @@ conversion_warning (tree type, tree expr)
   for (i = 0; i < expr_num_operands; i++)
     {
       tree op = TREE_OPERAND (expr, i);
-      if (DECL_P (op) && DECL_ARTIFICIAL (op))
+      if (op && DECL_P (op) && DECL_ARTIFICIAL (op))
 	return;
     }
 

gcc/testsuite/ChangeLog

 2008-08-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
 
+	PR 37217
+	* gcc.dg/pr37217.c: New.
+
+2008-08-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
+
 	PR c/31673
 	* gcc.dg/c90-fordecl-1.c: Update.
 

gcc/testsuite/gcc.dg/pr37217.c

+/* PR 37217 ICE with -Wconversion */
+/* { dg-do compile } */
+/* { dg-options "-Wconversion" } */
+typedef struct Tcl_ResolvedVarInfo {
+  char *re_guts;
+} regex_t;
+void TclReComp(regex_t *re)
+{
+  if (re->re_guts == ((void *)0)) ;
+}