re PR c/42570 (ICE in get_alias_set, at alias.c:710)

2010-01-01  Richard Guenther  <rguenther@suse.de>

	PR c/42570
	* c-decl.c (grokdeclarator): For zero-size arrays force
	structural equality checks as layout_type does.

	* gcc.c-torture/execute/pr42570.c: New testcase.

From-SVN: r155557

gcc/ChangeLog

+2010-01-01  Richard Guenther  <rguenther@suse.de>
+
+	PR c/42570
+	* c-decl.c (grokdeclarator): For zero-size arrays force
+	structural equality checks as layout_type does.
+
 2010-01-01  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* builtins.c: Update copyright to 2010.

gcc/c-decl.c

 /* Process declarations and variables for C compiler.
    Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
-   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
+   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
    Free Software Foundation, Inc.
 
 This file is part of GCC.
@@ -5394,6 +5394,7 @@ grokdeclarator (const struct c_declarator *declarator,
 		    gcc_assert (itype);
 		    TYPE_SIZE (type) = bitsize_zero_node;
 		    TYPE_SIZE_UNIT (type) = size_zero_node;
+		    SET_TYPE_STRUCTURAL_EQUALITY (type);
 		  }
 		if (array_parm_vla_unspec_p)
 		  {
@@ -5401,6 +5402,7 @@ grokdeclarator (const struct c_declarator *declarator,
 		    /* The type is complete.  C99 6.7.5.2p4  */
 		    TYPE_SIZE (type) = bitsize_zero_node;
 		    TYPE_SIZE_UNIT (type) = size_zero_node;
+		    SET_TYPE_STRUCTURAL_EQUALITY (type);
 		  }
 	      }
 

gcc/testsuite/ChangeLog

 2010-01-01  Richard Guenther  <rguenther@suse.de>
 
+	PR c/42570
+	* gcc.c-torture/execute/pr42570.c: New testcase.
+
+2010-01-01  Richard Guenther  <rguenther@suse.de>
+
 	PR middle-end/42559
 	* gcc.c-torture/compile/pr42559.c: New testcase.
 

gcc/testsuite/gcc.c-torture/execute/pr42570.c

+typedef unsigned char uint8_t;
+uint8_t foo[1][0];
+extern void abort (void);
+int main()
+{
+  if (sizeof (foo) != 0)
+    abort ();
+  return 0;
+}