[LTO]: PATCH: Avoid being confused by TRANSLATION_UNIT_DECL

[LTO]: PATCH: Avoid being confused by TRANSLATION_UNIT_DECL

[Mark Mitchell]

Kenny --

The problem that you ran into with structure types was due to the
DWARF writer not handling TRANSLATION_UNIT_DECL.  This patch fixes
that oversight.

However, trying to process this program in the LTO reader blows up in
build_decl for a local variable; it appears that you're creating a
VAR_DECL without giving it a type, and that makes the middle end
unhappy.

  struct S {
    int x;
    int y;
  };

  int foo (void) {
    struct S s;
    return s.x;
  }

Committed.

Thanks,

--
Mark Mitchell
CodeSourcery
mark@codesourcery.com
(650) 331-3385 x713

2007-08-05  Mark Mitchell  <mark@codesourcery.com>

	* tree.h (FILE_SCOPE_P): New macro.
	(DECL_FILE_SCOPE_P): Use it.
	* dwarf2out.c (lto_type_ref): Use FILE_SCOPE_P to test whether
	an entity is at file scope.

Index: gcc/tree.h
===================================================================
--- gcc/tree.h	(revision 127226)
+++ gcc/tree.h	(working copy)
@@ -2667,10 +2667,14 @@ struct tree_memory_partition_tag GTY(())
 #define DECL_POINTER_ALIAS_SET_KNOWN_P(NODE) \
   (DECL_POINTER_ALIAS_SET (NODE) != - 1)
 
+/* Nonzero for a scope (e.g., the value of either DECL_CONTEXT or
+   TYPE_CONTEXT) which is the file scope.  */
+#define FILE_SCOPE_P(SCOPE) \
+  (!(SCOPE) || TREE_CODE (SCOPE) == TRANSLATION_UNIT_DECL)
+
 /* Nonzero for a decl which is at file scope.  */
-#define DECL_FILE_SCOPE_P(EXP) 					\
-  (! DECL_CONTEXT (EXP)						\
-   || TREE_CODE (DECL_CONTEXT (EXP)) == TRANSLATION_UNIT_DECL)
+#define DECL_FILE_SCOPE_P(EXP) \
+  FILE_SCOPE_P (DECL_CONTEXT (EXP))					
 
 /* Nonzero for a decl that is decorated using attribute used.
    This indicates compiler tools that this decl needs to be preserved.  */
Index: gcc/dwarf2out.c
===================================================================
--- gcc/dwarf2out.c	(revision 127226)
+++ gcc/dwarf2out.c	(working copy)
@@ -14929,7 +14929,7 @@ lto_type_ref (tree type, lto_out_ref *re
   gcc_assert (TYPE_P (type));
 
   scope = TYPE_CONTEXT (type);
-  if (scope)
+  if (!FILE_SCOPE_P (scope))
     {
       /* We do not yet support lexically scoped types.  */
       sorry ("nested types are not supported by LTO");