Infrastructure & C front end changes for array parameter checking (PR c/50584).

gcc/ChangeLog:

	PR c/50584
	* attribs.c (decl_attributes): Also pass decl along with type
	attributes to handlers.
	(init_attr_rdwr_indices): Change second argument to attribute chain.
	Handle internal attribute representation in addition to external.
	(get_parm_access): New function.
	(attr_access::to_internal_string): Define new member function.
	(attr_access::to_external_string): Define new member function.
	(attr_access::vla_bounds): Define new member function.
	* attribs.h (struct attr_access): Declare new members.
	(attr_access::from_mode_char): Define new member function.
	(get_parm_access): Declare new function.
	* calls.c (initialize_argument_information): Pass function type
	attributes to init_attr_rdwr_indices.
	* doc/invoke.texi (-Warray-parameter, -Wvla-parameter): Document.
	* tree-pretty-print.c (dump_generic_node): Correct handling of
	qualifiers.
	* tree-ssa-uninit.c (maybe_warn_pass_by_reference): Same.
	* tree.h (access_mode): Add new enumerator.

gcc/c-family/ChangeLog:

	PR c/50584
	* c-attribs.c (c_common_attribute_table): Add "arg spec" attribute.
	(handle_argspec_attribute): New function.
	(get_argument, get_argument_type): New functions.
	(append_access_attrs): Add overload.  Handle internal attribute
	representation in addition to external.
	(handle_access_attribute): Handle internal attribute representation
	in addition to external.
	(build_attr_access_from_parms): New function.

gcc/c-family/ChangeLog:

	PR c/50584
	* c-common.h (warn_parm_array_mismatch): Declare new function.
	(has_attribute): Move declaration of an existing function.
	(build_attr_access_from_parms): Declare new function.
	* c-warn.c (parm_array_as_string): Define new function.
	(plus_one):  Define new function.
	(warn_parm_ptrarray_mismatch): Define new function.
	(warn_parm_array_mismatch):  Define new function.
	(vla_bound_parm_decl): New function.
	* c.opt (-Warray-parameter, -Wvla-parameter): New options.
	* c-pretty-print.c (pp_c_type_qualifier_list): Don't print array type
	qualifiers here...
	(c_pretty_printer::direct_abstract_declarator): ...but instead print
	them in brackets here.  Also print [static].  Strip extraneous
	expressions from VLA bounds.

gcc/c/ChangeLog:

	PR c/50584
	* c-decl.c (lookup_last_decl): Define new function.
	(c_decl_attributes): Call it.
	(start_decl): Add argument and use it.
	(finish_decl): Call build_attr_access_from_parms and decl_attributes.
	(get_parm_array_spec): Define new function.
	(push_parm_decl): Call get_parm_array_spec.
	(start_function): Call warn_parm_array_mismatch.  Build attribute
	access and add it to current function.
	* c-parser.c (c_parser_declaration_or_fndef): Diagnose mismatches
	in forms of array parameters.
	* c-tree.h (start_decl): Add argument.

gcc/testsuite/ChangeLog:

	PR c/50584
	* gcc.dg/attr-access-read-write-2.c: Adjust text of expected message.
	* c-c++-common/Warray-bounds-6.c: Correct C++ declaration, adjust
	text of expected diagnostics.
	* gcc.dg/Wbuiltin-declaration-mismatch-9.c: Prune expected warning.
	* gcc.dg/Warray-parameter-2.c: New test.
	* gcc.dg/Warray-parameter-3.c: New test.
	* gcc.dg/Warray-parameter-4.c: New test.
	* gcc.dg/Warray-parameter-5.c: New test.
	* gcc.dg/Warray-parameter.c: New test.
	* gcc.dg/Wvla-parameter-2.c: New test.
	* gcc.dg/Wvla-parameter-3.c: New test.
	* gcc.dg/Wvla-parameter.c: New test.

1 files changed, 17 insertions, 10 deletions

diff --git a/gcc/c/c-parser.c b/gcc/c/c-parser.c
index 2e6775a..7d58356 100644
--- a/gcc/c/c-parser.c
+++ b/gcc/c/c-parser.c
@@ -68,6 +68,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "intl.h"
 #include "c-family/name-hint.h"
 #include "tree-iterator.h"
+#include "tree-pretty-print.h"
 #include "memmodel.h"
 #include "c-family/known-headers.h"
 
@@ -2299,13 +2300,11 @@ c_parser_declaration_or_fndef (c_parser *parser, bool fndef_ok,
 		  c_parser_skip_to_end_of_block_or_statement (parser);
 		  return;
 		}
-	      tree d = start_decl (declarator, specs, false,
-				   chainon (postfix_attrs,
-					    all_prefix_attrs));
-	      if (d
-		  && TREE_CODE (d) == FUNCTION_DECL
-		  && DECL_ARGUMENTS (d) == NULL_TREE
-		  && DECL_INITIAL (d) == NULL_TREE)
+
+	      location_t lastloc = UNKNOWN_LOCATION;
+	      tree attrs = chainon (postfix_attrs, all_prefix_attrs);
+	      tree d = start_decl (declarator, specs, false, attrs, &lastloc);
+	      if (d && TREE_CODE (d) == FUNCTION_DECL)
 		{
 		  /* Find the innermost declarator that is neither cdk_id
 		     nor cdk_attrs.  */
@@ -2334,10 +2333,18 @@ c_parser_declaration_or_fndef (c_parser *parser, bool fndef_ok,
 			gcc_unreachable ();
 		      }
 
-		  /* If it exists and is cdk_function, use its parameters.  */
+		  /* If it exists and is cdk_function declaration whose
+		     arguments have not been set yet, use its arguments.  */
 		  if (last_non_id_attrs
 		      && last_non_id_attrs->kind == cdk_function)
-		    DECL_ARGUMENTS (d) = last_non_id_attrs->u.arg_info->parms;
+		    {
+		      tree parms = last_non_id_attrs->u.arg_info->parms;
+		      if (DECL_ARGUMENTS (d) == NULL_TREE
+			  && DECL_INITIAL (d) == NULL_TREE)
+			DECL_ARGUMENTS (d) = parms;
+
+		      warn_parm_array_mismatch (lastloc, d, parms);
+		    }
 		}
 	      if (omp_declare_simd_clauses.exists ())
 		{
@@ -2366,7 +2373,7 @@ c_parser_declaration_or_fndef (c_parser *parser, bool fndef_ok,
 	      if (d)
 		finish_decl (d, UNKNOWN_LOCATION, NULL_TREE,
 			     NULL_TREE, asm_name);
-	      
+
 	      if (c_parser_next_token_is_keyword (parser, RID_IN))
 		{
 		  if (d)