re PR c/34457 (ICE with VLA and -combine)

gcc/
	PR c/34457:
	* c-common.c (c_type_hash): Handle VLAs.
gcc/testsuite
	PR c/34457:
	* gcc.dg/pr34457-2.c: New file.
	* gcc.dg/pr34457-1.c: New file.

From-SVN: r131311

gcc/ChangeLog

+2008-01-03  Tom Tromey  <tromey@redhat.com>
+
+	PR c/34457:
+	* c-common.c (c_type_hash): Handle VLAs.
+
 2008-01-03  Jan Hubicka  <jh@suse.cz>
 
 	PR tree-optimization/31081

gcc/c-common.c

 /* Subroutines shared by all languages that are variants of C.
    Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
-   2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
+   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
 
 This file is part of GCC.
 
@@ -3171,7 +3171,11 @@ c_type_hash (const void *p)
     }
   for (; t2; t2 = TREE_CHAIN (t2))
     i++;
-  size = TREE_INT_CST_LOW (TYPE_SIZE (t));
+  /* We might have a VLA here.  */
+  if (TREE_CODE (TYPE_SIZE (t)) != INTEGER_CST)
+    size = 0;
+  else
+    size = TREE_INT_CST_LOW (TYPE_SIZE (t));
   return ((size << 24) | (i << shift));
 }
 

gcc/testsuite/ChangeLog

+2008-01-03  Tom Tromey  <tromey@redhat.com>
+
+	PR c/34457:
+	* gcc.dg/pr34457-2.c: New file.
+	* gcc.dg/pr34457-1.c: New file.
+
 2008-01-03  Sebastian Pop  <sebastian.pop@amd.com>
 
 	Revert fix for PR tree-optimization/34458.

gcc/testsuite/gcc.dg/pr34457-1.c

+/* PR c/34457 */
+/* { dg-do compile } */
+/* { dg-options "--combine -O2" } */
+/* { dg-additional-sources "pr34457-2.c" } */
+   
+
+typedef __SIZE_TYPE__ size_t;
+extern int printf (const char *, ...);
+extern void *memset (void *, int, size_t);
+
+int bar (int (*)(), int, void *);
+
+int
+main(int argc, char **argv)
+{
+  struct s { int a; char b[argc]; };
+  int nested (struct s x) { return x.a + sizeof(x); }
+  struct s t;
+  memset (&t, 0, sizeof(t));
+  t.a = 123;
+  printf("%d\n", bar (nested, argc, &t));
+  return 0;
+}

gcc/testsuite/gcc.dg/pr34457-2.c

+/* Additional file for PR c/34457.  */
+
+int x;