🚀 go-pugleaf

GCC doesn't issue a diagnostic for the empty struct declaration in the
program

	int main(c,v)
		struct s {int a;};
		int c;
		char **v;
	{ return 0; }
	
even though the program violates the following constraint, taken from ANSI
X3.159-1989, section 3.7.1, page 83, lines 7-8:

	If the declarator includes an identifier list, each declaration in the
	declaration list shall have at least one declarator ...

Here is a patch.

Sat Jul 25 00:41:12 1992  Paul Eggert  (eggert@twinsun.com)

	* c-parse.y (datadecl): Diagnose empty declarations in old-style
	function headers.
	* c-decl.c (shadow_tag_warned): New function.

===================================================================
RCS file: c-parse.y,v
retrieving revision 2.2
diff -c -r2.2 c-parse.y
*** c-parse.y	1992/05/21 18:08:40	2.2
--- c-parse.y	1992/07/25 00:04:28
***************
*** 581,587 ****
  		  declspec_stack = TREE_CHAIN (declspec_stack);
  		  resume_momentary ($2); }
  	| typed_declspecs ';'
! 		{ shadow_tag ($1); }
  	| declmods ';'
  		{ pedwarn ("empty declaration"); }
  	;
--- 581,588 ----
  		  declspec_stack = TREE_CHAIN (declspec_stack);
  		  resume_momentary ($2); }
  	| typed_declspecs ';'
! 		{ shadow_tag_warned ($1, 1);
! 		  pedwarn ("empty declaration"); }
  	| declmods ';'
  		{ pedwarn ("empty declaration"); }
  	;
===================================================================
RCS file: c-decl.c,v
retrieving revision 2.2.2.1
diff -c -r2.2.2.1 c-decl.c
*** c-decl.c	1992/06/21 05:34:02	2.2.2.1
--- c-decl.c	1992/07/25 00:13:45
***************
*** 388,393 ****
--- 388,394 ----
  static tree grokparms (), grokdeclarator ();
  tree pushdecl ();
  tree builtin_function ();
+ void shadow_tag_warned ();
  
  static tree lookup_tag ();
  static tree lookup_tag_reverse ();
***************
*** 2706,2713 ****
  shadow_tag (declspecs)
       tree declspecs;
  {
    int found_tag = 0;
-   int warned = 0;
    register tree link;
  
    pending_invalid_xref = 0;
--- 2707,2721 ----
  shadow_tag (declspecs)
       tree declspecs;
  {
+   shadow_tag_warned (declspecs, 0);
+ }
+ 
+ void
+ shadow_tag_warned (declspecs, warned)
+      tree declspecs;
+      int warned;
+ {
    int found_tag = 0;
    register tree link;
  
    pending_invalid_xref = 0;
***************
*** 2728,2734 ****
  
  	  if (name == 0)
  	    {
! 	      if (code != ENUMERAL_TYPE)	/* Empty unnamed enum OK */
  		{
  		  pedwarn ("unnamed struct/union that defines no instances");
  		  warned = 1;
--- 2736,2742 ----
  
  	  if (name == 0)
  	    {
! 	      if (!warned && code != ENUMERAL_TYPE) /* Empty unnamed enum OK */
  		{
  		  pedwarn ("unnamed struct/union that defines no instances");
  		  warned = 1;