[PATCH][LTO] Fix PRs 41808 and 41839

[Richard Guenther]

This fixes more gimple type verification errors with LTO.  The issue
is again completing pointer types.  We have no choice but to have
explicit conversions for conversions to incomplete pointed-to types
again - otherwise if we complete pointers from another TU we get
ICEs for the now invalid gimple IL.  I explored some other options
but they did not work.  The other thing is that we should use
struct tags for name comparison, not typedef names.

Bootstrapped and tested on x86_64-unknonw-linux-gnu, SPEC 2006 tested.

Ok for trunk?

Thanks,
Richard.

2009-10-27  Richard Guenther  <rguenther@suse.de>

	PR lto/41808
	PR lto/41839
	* tree-ssa.c (useless_type_conversion_p): Do not treat
	conversions to pointers to incomplete types as useless.
	* gimple.c (gimple_types_compatible_p): Compare struct tags,
	not typedef names.

	* gcc.dg/lto/20091027-1_0.c: New testcase.
	* gcc.dg/lto/20091027-1_1.c: Likewise.
	* g++.dg/lto/20091026-1_0.C: Likewise.
	* g++.dg/lto/20091026-1_1.C: Likewise.
	* g++.dg/lto/20091026-1_a.h: Likewise.

Index: trunk/gcc/tree-ssa.c
===================================================================
*** trunk.orig/gcc/tree-ssa.c	2009-10-27 10:42:09.000000000 +0100
--- trunk/gcc/tree-ssa.c	2009-10-27 10:43:43.000000000 +0100
*************** useless_type_conversion_p (tree outer_ty
*** 1201,1211 ****
  	 record type or a pointer to an unprototyped function,
  	 then the conversion is not necessary.  */
        if (VOID_TYPE_P (TREE_TYPE (outer_type))
- 	  || (AGGREGATE_TYPE_P (TREE_TYPE (outer_type))
- 	      && TREE_CODE (TREE_TYPE (outer_type)) != ARRAY_TYPE
- 	      && (TREE_CODE (TREE_TYPE (outer_type))
- 		  == TREE_CODE (TREE_TYPE (inner_type)))
- 	      && !COMPLETE_TYPE_P (TREE_TYPE (outer_type)))
  	  || ((TREE_CODE (TREE_TYPE (outer_type)) == FUNCTION_TYPE
  	       || TREE_CODE (TREE_TYPE (outer_type)) == METHOD_TYPE)
  	      && (TREE_CODE (TREE_TYPE (outer_type))
--- 1201,1206 ----
Index: trunk/gcc/gimple.c
===================================================================
*** trunk.orig/gcc/gimple.c	2009-10-27 10:56:48.000000000 +0100
--- trunk/gcc/gimple.c	2009-10-27 10:57:45.000000000 +0100
*************** gimple_types_compatible_p (tree t1, tree
*** 3357,3363 ****
  	    && RECORD_OR_UNION_TYPE_P (TREE_TYPE (t1))
  	    && (!COMPLETE_TYPE_P (TREE_TYPE (t1))
  		|| !COMPLETE_TYPE_P (TREE_TYPE (t2)))
! 	    && compare_type_names_p (TREE_TYPE (t1), TREE_TYPE (t2), true))
  	  {
  	    /* Replace the pointed-to incomplete type with the
  	       complete one.  */
--- 3357,3364 ----
  	    && RECORD_OR_UNION_TYPE_P (TREE_TYPE (t1))
  	    && (!COMPLETE_TYPE_P (TREE_TYPE (t1))
  		|| !COMPLETE_TYPE_P (TREE_TYPE (t2)))
! 	    && compare_type_names_p (TYPE_MAIN_VARIANT (TREE_TYPE (t1)),
! 				     TYPE_MAIN_VARIANT (TREE_TYPE (t2)), true))
  	  {
  	    /* Replace the pointed-to incomplete type with the
  	       complete one.  */
Index: trunk/gcc/testsuite/gcc.dg/lto/20091027-1_0.c
===================================================================
*** /dev/null	1970-01-01 00:00:00.000000000 +0000
--- trunk/gcc/testsuite/gcc.dg/lto/20091027-1_0.c	2009-10-27 11:01:32.000000000 +0100
***************
*** 0 ****
--- 1,11 ----
+ /* { dg-lto-do link } */
+ /* { dg-extra-ld-options "-r -nostdlib" } */
+ 
+ typedef struct _xmlDict xmlDict;
+ struct _xmlDict {
+  int ref_counter;
+ };
+ void xmlDictCreate(void) {
+   xmlDict * dict;
+ }
+ 
Index: trunk/gcc/testsuite/gcc.dg/lto/20091027-1_1.c
===================================================================
*** /dev/null	1970-01-01 00:00:00.000000000 +0000
--- trunk/gcc/testsuite/gcc.dg/lto/20091027-1_1.c	2009-10-27 11:01:59.000000000 +0100
***************
*** 0 ****
--- 1,9 ----
+ typedef struct _xmlDict xmlDict;
+ struct _xmlDoc {
+   struct _xmlDict *dict;
+ };
+ void xmlAddEntity(struct _xmlDoc *a) {
+   xmlDict * dict = a->dict;
+   xmlHashCreateDict(0, dict);
+ }
+ 
Index: trunk/gcc/testsuite/g++.dg/lto/20091026-1_0.C
===================================================================
*** /dev/null	1970-01-01 00:00:00.000000000 +0000
--- trunk/gcc/testsuite/g++.dg/lto/20091026-1_0.C	2009-10-26 14:48:08.000000000 +0100
***************
*** 0 ****
--- 1,11 ----
+ // { dg-lto-do link }
+ // { dg-extra-ld-options "-r -nostdlib" }
+ 
+ #include "20091026-1_a.h"
+ cObject *cHead::find(const char *objname) const
+ {
+     return firstchildp;
+ }
+ class cNetworkType : public cObject { };
+ cNetworkType *networktype;
+ 
Index: trunk/gcc/testsuite/g++.dg/lto/20091026-1_1.C
===================================================================
*** /dev/null	1970-01-01 00:00:00.000000000 +0000
--- trunk/gcc/testsuite/g++.dg/lto/20091026-1_1.C	2009-10-26 15:51:24.000000000 +0100
***************
*** 0 ****
--- 1,14 ----
+ #include "20091026-1_a.h"
+ extern cHead networks;
+ class cNetworkType;
+ inline cNetworkType *findNetwork(const char *s)
+ {
+   return (cNetworkType *)networks.find(s);
+ }
+ int run(const char *opt_network_name)
+ {
+   cNetworkType *network = findNetwork(opt_network_name);
+   if (!network)
+     throw 1;
+ }
+ 
Index: trunk/gcc/testsuite/g++.dg/lto/20091026-1_a.h
===================================================================
*** /dev/null	1970-01-01 00:00:00.000000000 +0000
--- trunk/gcc/testsuite/g++.dg/lto/20091026-1_a.h	2009-10-26 14:48:35.000000000 +0100
***************
*** 0 ****
--- 1,9 ----
+ class cObject {
+ public:
+     cObject *firstchildp;
+ };
+ class cHead : public cObject {
+ public:
+     cObject *find(const char *objname) const;
+ };
+