Patch for bug 16667

[Joseph S. Myers]

This patch fixes bug 16667, reporting that an undocumented hybrid form
of old GNU-style designated initializers and C99-style designated
initializers, ".foo" field designators without "=", was wrongly
accepted.  I've of course made a corresponding change to my new
parser.  This saves adding testcases that this hybrid form is accepted
when writing/generating tests that the new and old parsers accept the
same language.

Since this hybrid form was never documented, having been added
accidentally by Drepper's patch
<http://gcc.gnu.org/ml/gcc-patches/1998-11/msg00302.html> (committed
version: <http://gcc.gnu.org/ml/gcc-patches/1998-12/msg00001.html>), I
consider it safe to remove as a bug fix rather than requiring a
deprecation period as would properly deprecating all uses of old-style
designated initializers.

Bootstrapped with no regressions on i686-pc-linux-gnu.  Applied to
mainline.

-- 
Joseph S. Myers               http://www.srcf.ucam.org/~jsm28/gcc/
    jsm@polyomino.org.uk (personal mail)
    joseph@codesourcery.com (CodeSourcery mail)
    jsm28@gcc.gnu.org (Bugzilla assignments and CCs)

2004-10-25  Joseph S. Myers  <jsm@polyomino.org.uk>

	PR c/16667
	* c-parse.in (array_designator): New.
	(designator): Use it.
	(initelt): Only permit array_designator without '=', not ".foo".

2004-10-25  Joseph S. Myers  <jsm@polyomino.org.uk>

	PR c/16667
	* gcc.dg/init-desig-obs-1.c, gcc.dg/init-desig-obs-2.c,
	gcc.dg/init-desig-obs-3.c: New tests.

diff -rupN GCC.orig/gcc/c-parse.in GCC/gcc/c-parse.in
--- GCC.orig/gcc/c-parse.in	2004-10-19 19:40:51.000000000 +0000
+++ GCC/gcc/c-parse.in	2004-10-25 13:03:51.000000000 +0000
@@ -1445,7 +1445,7 @@ initelt:
 	  designator_list '=' initval
 		{ if (pedantic && !flag_isoc99)
 		    pedwarn ("ISO C90 forbids specifying subobject to initialize"); }
-	| designator initval
+	| array_designator initval
 		{ if (pedantic)
 		    pedwarn ("obsolete use of designated initializer without %<=%>"); }
 	| identifier ':'
@@ -1475,7 +1475,10 @@ designator_list:
 designator:
 	  '.' identifier
 		{ set_init_label ($2); }
-	| '[' expr_no_commas ELLIPSIS expr_no_commas ']'
+	| array_designator
+
+array_designator:
+	  '[' expr_no_commas ELLIPSIS expr_no_commas ']'
 		{ set_init_index ($2.value, $4.value);
 		  if (pedantic)
 		    pedwarn ("ISO C forbids specifying range of elements to initialize"); }
diff -rupN GCC.orig/gcc/testsuite/gcc.dg/init-desig-obs-1.c GCC/gcc/testsuite/gcc.dg/init-desig-obs-1.c
--- GCC.orig/gcc/testsuite/gcc.dg/init-desig-obs-1.c	1970-01-01 00:00:00.000000000 +0000
+++ GCC/gcc/testsuite/gcc.dg/init-desig-obs-1.c	2004-10-25 12:58:53.000000000 +0000
@@ -0,0 +1,19 @@
+/* Test obsolete forms of designated initializers.  Test with default
+   warning options: valid forms are accepted, while ".member" without
+   "=" should not be (bug 16667).  */
+/* Origin: Joseph Myers <jsm@polyomino.org.uk> */
+/* { dg-do compile } */
+/* { dg-options "" } */
+struct s { int a; };
+struct s s0 = { .a = 1 };
+struct s s1 = { a: 1 };
+
+int x0[] = { [0] = 1 };
+int x1[] = { [0] 1 };
+
+/* Invalid syntax: multiple designators without "=".  */
+int x2[2][2] = { [0][0] 1 }; /* { dg-error "(syntax|parse) error" } */
+
+
+/* Invalid syntax: C99-style structure designator without "=".  */
+struct s s2 = { .a 1 }; /* { dg-error "(syntax|parse) error" } */
diff -rupN GCC.orig/gcc/testsuite/gcc.dg/init-desig-obs-2.c GCC/gcc/testsuite/gcc.dg/init-desig-obs-2.c
--- GCC.orig/gcc/testsuite/gcc.dg/init-desig-obs-2.c	1970-01-01 00:00:00.000000000 +0000
+++ GCC/gcc/testsuite/gcc.dg/init-desig-obs-2.c	2004-10-25 13:00:16.000000000 +0000
@@ -0,0 +1,11 @@
+/* Test obsolete forms of designated initializers.  Test with
+   -pedantic.  */
+/* Origin: Joseph Myers <jsm@polyomino.org.uk> */
+/* { dg-do compile } */
+/* { dg-options "-std=gnu99 -pedantic" } */
+struct s { int a; };
+struct s s0 = { .a = 1 };
+struct s s1 = { a: 1 }; /* { dg-warning "warning: obsolete use of designated initializer with ':'" } */
+
+int x0[] = { [0] = 1 };
+int x1[] = { [0] 1 }; /* { dg-warning "warning: obsolete use of designated initializer without '='" } */
diff -rupN GCC.orig/gcc/testsuite/gcc.dg/init-desig-obs-3.c GCC/gcc/testsuite/gcc.dg/init-desig-obs-3.c
--- GCC.orig/gcc/testsuite/gcc.dg/init-desig-obs-3.c	1970-01-01 00:00:00.000000000 +0000
+++ GCC/gcc/testsuite/gcc.dg/init-desig-obs-3.c	2004-10-25 13:00:34.000000000 +0000
@@ -0,0 +1,11 @@
+/* Test obsolete forms of designated initializers.  Test with
+   -pedantic-errors.  */
+/* Origin: Joseph Myers <jsm@polyomino.org.uk> */
+/* { dg-do compile } */
+/* { dg-options "-std=gnu99 -pedantic-errors" } */
+struct s { int a; };
+struct s s0 = { .a = 1 };
+struct s s1 = { a: 1 }; /* { dg-error "error: obsolete use of designated initializer with ':'" } */
+
+int x0[] = { [0] = 1 };
+int x1[] = { [0] 1 }; /* { dg-error "error: obsolete use of designated initializer without '='" } */