c-typeck.c (lookup_field): If -fplan9-extensions, permit referring to a field using a typedef name.

gcc/:
	* c-typeck.c (lookup_field): If -fplan9-extensions, permit
	referring to a field using a typedef name.
	(find_anonymous_field_with_type): New static function.
	(convert_to_anonymous_field): New static function.
	(convert_for_assignment): If -fplan9-extensions, permit converting
	pointer to struct to pointer to anonymous field.
	* c-decl.c (grokfield): If -fplan9-extensions, permit anonymous
	fields.
	(is_duplicate_field): New static function.
	(detect_field_duplicates_hash): If -fplan9-extensions, check for
	typedef names duplicating field names.
	(detect_field_duplicates): Likewise.
	* doc/invoke.texi (Option Summary): Mention -fplan9-extensions.
	(C Dialect Options): Document -fplan9-extensions.
	* doc/extend.texi (Unnamed Fields): Document -fplan9-extensions.
gcc/c-family/:
	* c.opt (-fplan9-extensions): New option.
gcc/testsuite/:
	* gcc.dg/anon-struct-11.c: New test.
	* gcc.dg/anon-struct-12.c: New test.
	* gcc.dg/anon-struct-13.c: New test.
	* gcc.dg/anon-struct-14.c: New test.

From-SVN: r164926

1 files changed, 9 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.dg/anon-struct-14.c b/gcc/testsuite/gcc.dg/anon-struct-14.c
new file mode 100644
index 0000000..293ccc7
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/anon-struct-14.c
@@ -0,0 +1,9 @@
+/* { dg-do compile } */
+/* { dg-options "-fplan9-extensions" } */
+
+/* When using Plan 9 extensions, a typedef can conflict with an
+   anonymous field.  */
+
+typedef struct { int a; } s1;
+struct s2 { s1; int s1; };		/* { dg-error "duplicate" } */
+int f(struct s2 *p) { return p->s1; }	/* { dg-error "incompatible" } */