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, 57 insertions, 4 deletions

diff --git a/gcc/c-family/c-pretty-print.c b/gcc/c-family/c-pretty-print.c
index c364e1c..acffd7b 100644
--- a/gcc/c-family/c-pretty-print.c
+++ b/gcc/c-family/c-pretty-print.c
@@ -248,9 +248,12 @@ pp_c_type_qualifier_list (c_pretty_printer *pp, tree t)
   if (!TYPE_P (t))
     t = TREE_TYPE (t);
 
-  qualifiers = TYPE_QUALS (t);
-  pp_c_cv_qualifiers (pp, qualifiers,
-		      TREE_CODE (t) == FUNCTION_TYPE);
+  if (TREE_CODE (t) != ARRAY_TYPE)
+    {
+      qualifiers = TYPE_QUALS (t);
+      pp_c_cv_qualifiers (pp, qualifiers,
+			  TREE_CODE (t) == FUNCTION_TYPE);
+    }
 
   if (!ADDR_SPACE_GENERIC_P (TYPE_ADDR_SPACE (t)))
     {
@@ -572,6 +575,8 @@ c_pretty_printer::abstract_declarator (tree t)
 void
 c_pretty_printer::direct_abstract_declarator (tree t)
 {
+  bool add_space = false;
+
   switch (TREE_CODE (t))
     {
     case POINTER_TYPE:
@@ -585,17 +590,65 @@ c_pretty_printer::direct_abstract_declarator (tree t)
 
     case ARRAY_TYPE:
       pp_c_left_bracket (this);
+
+      if (int quals = TYPE_QUALS (t))
+	{
+	  /* Print the array qualifiers such as in "T[const restrict 3]".  */
+	  pp_c_cv_qualifiers (this, quals, false);
+	  add_space = true;
+	}
+
+      if (tree arr = lookup_attribute ("array", TYPE_ATTRIBUTES (t)))
+	{
+	  if (TREE_VALUE (arr))
+	    {
+	      /* Print the specifier as in "T[static 3]" that's not actually
+		 part of the type but may be added by the front end.  */
+	      pp_c_ws_string (this, "static");
+	      add_space = true;
+	    }
+	  else if (!TYPE_DOMAIN (t))
+	    /* For arrays of unspecified bound using the [*] notation. */
+	    pp_character (this, '*');
+	}
+
       if (tree dom = TYPE_DOMAIN (t))
 	{
 	  if (tree maxval = TYPE_MAX_VALUE (dom))
 	    {
+	      if (add_space)
+		pp_space (this);
+
 	      tree type = TREE_TYPE (maxval);
 
 	      if (tree_fits_shwi_p (maxval))
 		pp_wide_integer (this, tree_to_shwi (maxval) + 1);
-	      else
+	      else if (TREE_CODE (maxval) == INTEGER_CST)
 		expression (fold_build2 (PLUS_EXPR, type, maxval,
 					 build_int_cst (type, 1)));
+	      else
+		{
+		  /* Strip the expressions from around a VLA bound added
+		     internally to make it fit the domain mold, including
+		     any casts.  */
+		  if (TREE_CODE (maxval) == NOP_EXPR)
+		    maxval = TREE_OPERAND (maxval, 0);
+		  if (TREE_CODE (maxval) == PLUS_EXPR
+		      && integer_all_onesp (TREE_OPERAND (maxval, 1)))
+		    {
+		      maxval = TREE_OPERAND (maxval, 0);
+		      if (TREE_CODE (maxval) == NOP_EXPR)
+			maxval = TREE_OPERAND (maxval, 0);
+		    }
+		  if (TREE_CODE (maxval) == SAVE_EXPR)
+		    {
+		      maxval = TREE_OPERAND (maxval, 0);
+		      if (TREE_CODE (maxval) == NOP_EXPR)
+			maxval = TREE_OPERAND (maxval, 0);
+		    }
+
+		  expression (maxval);
+		}
 	    }
 	  else if (TYPE_SIZE (t))
 	    /* Print zero for zero-length arrays but not for flexible