c-tree.h (lang_decl): Add pending_sizes fields.

	* c-tree.h (lang_decl): Add pending_sizes fields.
	* c-decl.c (store_parm_decls): Save pending_sizes away for nested
	functions.
	(c_expand_body): Expand them.
	(lang_mark_tree): Mark lang_decl:pending_sizes.
	* function.c (expand_pending_sizes): New function, broken out
	from ...
	(expand_function_start): ... here.
	* tree.h (expand_pending_sizes): Declare it.

From-SVN: r42892

gcc/ChangeLog

+2001-06-04  Mark Mitchell  <mark@codesourcery.com>
+
+	* c-tree.h (lang_decl): Add pending_sizes fields.
+	* c-decl.c (store_parm_decls): Save pending_sizes away for nested
+	functions.
+	(c_expand_body): Expand them.
+	(lang_mark_tree): Mark lang_decl:pending_sizes.
+	* function.c (expand_pending_sizes): New function, broken out 
+	from ...
+	(expand_function_start): ... here.
+	* tree.h (expand_pending_sizes): Declare it.
+	
 2001-06-04  Loren J. Rittle  <ljrittle@acm.org>
 
 	* doc/install.texi: Update FreeBSD information.  Generalize

gcc/c-decl.c

@@ -6167,6 +6167,9 @@ store_parm_decls ()
   /* Nonzero if this definition is written with a prototype.  */
   int prototype = 0;
 
+  /* The function containing FNDECL, if any.  */
+  tree context = decl_function_context (fndecl);
+
   if (specparms != 0 && TREE_CODE (specparms) != TREE_LIST)
     {
       /* This case is when the function was defined with an ANSI prototype.
@@ -6534,14 +6537,28 @@ store_parm_decls ()
   gen_aux_info_record (fndecl, 1, 0, prototype);
 
   /* Initialize the RTL code for the function.  */
-
   init_function_start (fndecl, input_filename, lineno);
 
   /* Begin the statement tree for this function.  */
   DECL_LANG_SPECIFIC (current_function_decl)
-    =((struct lang_decl *) ggc_alloc (sizeof (struct lang_decl)));
+    =((struct lang_decl *) ggc_alloc_cleared (sizeof (struct lang_decl)));
   begin_stmt_tree (&DECL_SAVED_TREE (current_function_decl));
 
+  /* If this is a nested function, save away the sizes of any
+     variable-size types so that we can expand them when generating
+     RTL.  */
+  if (context)
+    {
+      tree t;
+
+      DECL_LANG_SPECIFIC (fndecl)->pending_sizes 
+	= nreverse (get_pending_sizes ());
+      for (t = DECL_LANG_SPECIFIC (fndecl)->pending_sizes;
+	   t;
+	   t = TREE_CHAIN (t))
+	SAVE_EXPR_CONTEXT (TREE_VALUE (t)) = context;
+    }
+
   /* This function is being processed in whole-function mode.  */
   cfun->x_whole_function_mode_p = 1;
 
@@ -6786,9 +6803,14 @@ c_expand_body (fndecl, nested_p)
   if (flag_syntax_only)
     return;
 
-  /* Squirrel away our current state.  */
   if (nested_p)
-    push_function_context ();
+    {
+      /* Make sure that we will evaluate variable-sized types involved
+	 in our function's type.  */
+      expand_pending_sizes (DECL_LANG_SPECIFIC (fndecl)->pending_sizes);
+      /* Squirrel away our current state.  */
+      push_function_context ();
+    }
 
   /* Initialize the RTL code for the function.  */
   current_function_decl = fndecl;
@@ -6823,7 +6845,7 @@ c_expand_body (fndecl, nested_p)
   /* Allow the body of the function to be garbage collected.  */
   DECL_SAVED_TREE (fndecl) = NULL_TREE;
 
-  /* We hard-wired immediate_size_expand to zero in start_function.
+  /* We hard-wired immediate_size_expand to zero above.
      expand_function_end will decrement this variable.  So, we set the
      variable to one here, so that after the decrement it will remain
      zero.  */
@@ -7116,6 +7138,7 @@ lang_mark_tree (t)
     {
       ggc_mark (DECL_LANG_SPECIFIC (t));
       c_mark_lang_decl (&DECL_LANG_SPECIFIC (t)->base);
+      ggc_mark_tree (DECL_LANG_SPECIFIC (t)->pending_sizes);
     }
 }
 

gcc/c-tree.h

@@ -41,12 +41,15 @@ struct lang_identifier
   tree error_locus, limbo_value;
 };
 
-/* Wrapping c_lang_decl in another struct is an unfortunate
-   necessity.  */
+/* Language-specific declaration information.  */
 
 struct lang_decl
 {
   struct c_lang_decl base;
+  /* The return types and parameter types may have variable size.
+     This is a list of any SAVE_EXPRs that need to be evaluated to
+     compute those sizes.  */
+  tree pending_sizes;
 };
 
 /* Macros for access to language-specific slots in an identifier.  */

gcc/function.c

@@ -6270,6 +6270,29 @@ expand_main_function ()
 
 extern struct obstack permanent_obstack;
 
+/* The PENDING_SIZES represent the sizes of variable-sized types.
+   Create RTL for the various sizes now (using temporary variables),
+   so that we can refer to the sizes from the RTL we are generating
+   for the current function.  The PENDING_SIZES are a TREE_LIST.  The
+   TREE_VALUE of each node is a SAVE_EXPR.  */
+
+void
+expand_pending_sizes (pending_sizes)
+     tree pending_sizes;
+{
+  tree tem;
+
+  /* Evaluate now the sizes of any types declared among the arguments.  */
+  for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
+    {
+      expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
+		   EXPAND_MEMORY_USE_BAD);
+      /* Flush the queue in case this parameter declaration has
+	 side-effects.  */
+      emit_queue ();
+    }
+}
+
 /* Start the RTL for a new function, and set variables used for
    emitting RTL.
    SUBR is the FUNCTION_DECL node.
@@ -6487,14 +6510,7 @@ expand_function_start (subr, parms_have_cleanups)
   tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
 
   /* Evaluate now the sizes of any types declared among the arguments.  */
-  for (tem = nreverse (get_pending_sizes ()); tem; tem = TREE_CHAIN (tem))
-    {
-      expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
-		   EXPAND_MEMORY_USE_BAD);
-      /* Flush the queue in case this parameter declaration has
-	 side-effects.  */
-      emit_queue ();
-    }
+  expand_pending_sizes (nreverse (get_pending_sizes ()));
 
   /* Make sure there is a line number after the function entry setup code.  */
   force_next_line_note ();

gcc/testsuite/gcc.c-torture/compile/20010605-1.c

+int
+main (int argc, char **argv)
+{
+  int size = 10;
+
+  typedef struct {
+    char val[size];
+  } block;
+  block retframe_block()
+    {
+      return *(block*)0;
+    }
+
+  return 0;
+}

gcc/tree.h

@@ -2720,6 +2720,7 @@ extern void print_obstack_name		PARAMS ((char *, FILE *,
 #endif
 extern void expand_function_end		PARAMS ((const char *, int, int));
 extern void expand_function_start	PARAMS ((tree, int));
+extern void expand_pending_sizes        PARAMS ((tree));
 
 extern int real_onep			PARAMS ((tree));
 extern int real_twop			PARAMS ((tree));