Fix up vla, vm and [*] sematics.

	PR c/18740
	PR c/7948
	PR c/25802
	* c-tree.h (struct c_arg_info): Add had_vla_unspec.
	(c_vla_unspec_p): Add.
	(c_vla_type_p): Add.
	* c-decl.c (struct c_scope): Add had_vla_unspec.
	(build_array_declarator): Add support for [*].
	(grokdeclarator): Likewise.
	(grokparms): Likewise.
	(get_parm_info): Likewise.
	* c-objc-common.c (c_vla_unspec_p): Likewise.
	* c-objc-common.h (LANG_HOOKS_TREE_INLINING_VAR_MOD_TYPE_P): Likewise.
	* c-parser.c (c_parser_typeof_specifier): Evaluate arguments to
	typeof when argument is a variably modified type not inside sizeof or alignof.
	(c_parser_direct_declarator_inner): Propagate errors.
	(c_parser_sizeof_expression): Add support for [*].
	* c-typeck.c (c_vla_type_p): Add.
	(composite_type): Add support for vla compositing.
	(comptypes_internal): Add support for vla compatibility.
	(c_expr_sizeof_expr): Evaluate vla arguments.
	* tree.c (variably_modified_type_p): Update comment for [*].

testsuite:
	* gcc.dg/c90-arraydecl-1.c: Update for vla, vm [*] fixups.
	* gcc.dg/vla-4.c: Add.
	* gcc.dg/vla-5.c: Add.
	* gcc.dg/vla-6.c: Add.

From-SVN: r113888

1 files changed, 16 insertions, 1 deletions

diff --git a/gcc/c-parser.c b/gcc/c-parser.c
index 8f6cafd..5a67653 100644
--- a/gcc/c-parser.c
+++ b/gcc/c-parser.c
@@ -2148,6 +2148,7 @@ c_parser_typeof_specifier (c_parser *parser)
     }
   else
     {
+      bool was_vm;
       struct c_expr expr = c_parser_expression (parser);
       skip_evaluation--;
       in_typeof--;
@@ -2155,7 +2156,13 @@ c_parser_typeof_specifier (c_parser *parser)
 	  && DECL_C_BIT_FIELD (TREE_OPERAND (expr.value, 1)))
 	error ("%<typeof%> applied to a bit-field");
       ret.spec = TREE_TYPE (expr.value);
-      pop_maybe_used (variably_modified_type_p (ret.spec, NULL_TREE));
+      was_vm = variably_modified_type_p (ret.spec, NULL_TREE);
+      /* This should be returned with the type so that when the type
+	 is evaluated, this can be evaluated.  For now, we avoid
+	 evaluation when the context might.  */
+      if (!skip_evaluation && was_vm)
+	c_finish_expr_stmt (expr.value);
+      pop_maybe_used (was_vm);
     }
   c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, "expected %<)%>");
   return ret;
@@ -2451,6 +2458,8 @@ c_parser_direct_declarator_inner (c_parser *parser, bool id_present,
 	}
       declarator = build_array_declarator (dimen, quals_attrs, static_seen,
 					   star_seen);
+      if (declarator == NULL)
+	return NULL;
       inner = set_array_declarator_inner (declarator, inner, !id_present);
       return c_parser_direct_declarator_inner (parser, id_present, inner);
     }
@@ -4868,6 +4877,12 @@ c_parser_sizeof_expression (c_parser *parser)
       /* sizeof ( type-name ).  */
       skip_evaluation--;
       in_sizeof--;
+      if (type_name->declarator->kind == cdk_array
+	  && type_name->declarator->u.array.vla_unspec_p)
+	{
+	  /* C99 6.7.5.2p4 */
+	  error ("%<[*]%> not allowed in other than a declaration");
+	}
       return c_expr_sizeof_type (type_name);
     }
   else