PR middle-end/83859 - attributes to associate pointer arguments and sizes

gcc/ChangeLog:

	PR middle-end/83859
	* attribs.h (struct attr_access): New.
	* attribs.c (decl_attributes): Add an informational note.
	* builtins.c (check_access): Make extern.  Consistently set no-warning
	after issuing a warning.  Handle calls through function pointers.  Set
	no-warning.
	* builtins.h (check_access): Declare.
	* calls.c (rdwr_access_hash): New type.
	(rdwr_map): Same.
	(init_attr_rdwr_indices): New function.
	(maybe_warn_rdwr_sizes): Same.
	(initialize_argument_information): Call init_attr_rdwr_indices.
	Call maybe_warn_rdwr_sizes.
	(get_size_range): Avoid null argument.
	* doc/extend.texi (attribute access): Document new attribute.

gcc/c-family/ChangeLog:

	PR middle-end/83859
	* c-attribs.c (handle_access_attribute): New function.
	(c_common_attribute_table): Add new attribute.
	(get_argument_type): New function.
	(append_access_attrs): New function.
	(get_nonnull_operand): Rename...
	(get_attribute_operand): ...to this.
	* c-common.c (get_nonnull_operand): Rename...
	(get_attribute_operand): ...to this.

gcc/testsuite/ChangeLog:

	PR middle-end/83859
	* c-c++-common/attr-nonstring-8.c: Adjust text of expected warning.
	* gcc.dg/Wstringop-overflow-23.c: New test.
	* gcc.dg/Wstringop-overflow-24.c: New test.
	* gcc.dg/attr-access-read-only.c: New test.
	* gcc.dg/attr-access-read-write.c: New test.
	* gcc.dg/attr-access-read-write-2.c: New test.
	* gcc.dg/attr-access-write-only.c: New test.

From-SVN: r278624

1 files changed, 20 insertions, 0 deletions

diff --git a/gcc/attribs.h b/gcc/attribs.h
index 23a7321e04a..9bc1600dfe3 100644
--- a/gcc/attribs.h
+++ b/gcc/attribs.h
@@ -218,4 +218,24 @@ lookup_attribute_by_prefix (const char *attr_name, tree list)
     }
 }
 
+/* Description of a function argument declared with attribute access.
+   Used as an "iterator" over all such arguments in a function declaration
+   or call.  */
+
+struct attr_access
+{
+  /* The attribute pointer argument.  */
+  tree ptr;
+  /* The size of the pointed-to object or NULL when not specified.  */
+  tree size;
+
+  /* The zero-based number of each of the formal function arguments.  */
+  unsigned ptrarg;
+  unsigned sizarg;
+
+  /* The access mode.  */
+  enum access_mode { read_only, write_only, read_write };
+  access_mode mode;
+};
+
 #endif // GCC_ATTRIBS_H