cpplex.c (parse_args): Don't set VOID_REST flag.

        * cpplex.c (parse_args): Don't set VOID_REST flag.
	(Fix diagnostic merge problem).
        (CONTEXT_VARARGS): New flag.
        (maybe_paste_with_next): Set context earlier in loop.  Use
        it.  Do varargs test with CONTEXT_VARARGS flag.
        (push_arg_context): Set CONTEXT_VARARGS flag if we're
        pushing an argument context for a varargs argument.
        * cpplib.h (VOID_REST): Delete.
        * gcc.dg/cpp/vararg1.c: Add test case.

From-SVN: r36638

4 files changed, 34 insertions, 30 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d2a5f1e..3b3a6f2 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,14 @@
+Tue 26-Sep-2000 00:16:22 BST  Neil Booth  <neilb@earthling.net>
+
+        * cpplex.c (parse_args): Don't set VOID_REST flag.
+	(CONTEXT_VARARGS): New flag.
+	(maybe_paste_with_next): Set context earlier in loop.  Use
+	it.  Do varargs test with CONTEXT_VARARGS flag.
+	(push_arg_context): Set CONTEXT_VARARGS flag if we're
+	pushing an argument context for a varargs argument.
+	* cpplib.h (VOID_REST): Delete.
+	* gcc.dg/cpp/vararg1.c: Add test case.   
+
 2000-09-25  Branko Cibej  <branko.cibej@hermes.si>
 
         * flags.h:  Declare warning flag warn_system_headers.
diff --git a/gcc/cpplex.c b/gcc/cpplex.c
index 47dcdbc..4b2f84b 100644
--- a/gcc/cpplex.c
+++ b/gcc/cpplex.c
@@ -52,6 +52,7 @@ static const cpp_token eof_token = {0, 0, CPP_EOF, 0 UNION_INIT_ZERO};
 #define CONTEXT_PASTER	(1 << 1) /* An argument context on RHS of ##.  */
 #define CONTEXT_RAW	(1 << 2) /* If argument tokens already expanded.  */
 #define CONTEXT_ARG	(1 << 3) /* If an argument context.  */
+#define CONTEXT_VARARGS	(1 << 4) /* If a varargs argument context.  */
 
 typedef struct cpp_context cpp_context;
 struct cpp_context
@@ -1209,24 +1210,9 @@ lex_token (pfile, result)
 	     irrespective of conformance mode, because lots of
 	     broken systems do that and trying to clean it up in
 	     fixincludes is a nightmare.  */
-	  if (CPP_OPTION (pfile, cplusplus_comments)
-	      || CPP_IN_SYSTEM_HEADER (pfile))
+	  if (CPP_OPTION (pfile, c89) && CPP_PEDANTIC (pfile)
+	      && ! buffer->warned_cplusplus_comments)
 	    {
-	      if (CPP_OPTION (pfile, c89) && CPP_PEDANTIC (pfile)
-		  && ! buffer->warned_cplusplus_comments)
-		{
-		  cpp_pedwarn (pfile,
-		       "C++ style comments are not allowed in ISO C89");
-		  cpp_pedwarn (pfile,
-		       "(this will be reported only once per input file)");
-		  buffer->warned_cplusplus_comments = 1;
-		}
-	      comment_start = buffer->cur;
-
-	      /* Skip_line_comment updates buffer->read_ahead.  */
-	      if (skip_line_comment (pfile))
-		cpp_warning_with_line (pfile, result->line, result->col,
-				       "multi-line comment");
 	      cpp_pedwarn (pfile,
 			   "C++ style comments are not allowed in ISO C89");
 	      cpp_pedwarn (pfile,
@@ -1234,6 +1220,7 @@ lex_token (pfile, result)
 	      buffer->warned_cplusplus_comments = 1;
 	    }
 
+	  /* Skip_line_comment updates buffer->read_ahead.  */
 	  if (skip_line_comment (pfile))
 	    cpp_warning_with_line (pfile, result->line, result->col,
 				   "multi-line comment");
@@ -2004,9 +1991,7 @@ parse_args (pfile, hp, args)
 	{
 	  /* Duplicate the placemarker.  Then we can set its flags and
              position and safely be using more than one.  */
-	  cpp_token *pm = duplicate_token (pfile, &placemarker_token);
-	  pm->flags = VOID_REST;
-	  save_token (args, pm);
+	  save_token (args, duplicate_token (pfile, &placemarker_token));
 	  args->ends[argc] = total + 1;
 
 	  if (CPP_OPTION (pfile, c99) && CPP_PEDANTIC (pfile))
@@ -2316,6 +2301,7 @@ maybe_paste_with_next (pfile, token)
       pfile->paste_level = pfile->cur_context;
       second = _cpp_get_token (pfile);
       pfile->paste_level = 0;
+      context = CURRENT_CONTEXT (pfile);
 
       /* Ignore placemarker argument tokens (cannot be from an empty
 	 macro since macros are not expanded).  */
@@ -2327,7 +2313,7 @@ maybe_paste_with_next (pfile, token)
 	     a varargs parameter: the comma disappears if b was given
 	     no actual arguments (not merely if b is an empty
 	     argument).  */
-	  if (token->type == CPP_COMMA && second->flags & VOID_REST)
+	  if (token->type == CPP_COMMA && (context->flags & CONTEXT_VARARGS))
 	    pasted = duplicate_token (pfile, second);
 	  else
 	    pasted = duplicate_token (pfile, token);
@@ -2345,9 +2331,8 @@ maybe_paste_with_next (pfile, token)
 		     <whatever> came from a variable argument, because
 		     the author probably intended the ## to trigger
 		     the special extended semantics (see above).  */
-		  if (token->type == CPP_COMMA
-		      && IS_ARG_CONTEXT (CURRENT_CONTEXT (pfile))
-		      && ON_REST_ARG (CURRENT_CONTEXT (pfile) - 1))
+		  if (token->type == CPP_COMMA && IS_ARG_CONTEXT (context)
+		      && ON_REST_ARG (context - 1))
 		    /* no warning */;
 		  else
 		    cpp_warning (pfile,
@@ -2411,7 +2396,6 @@ maybe_paste_with_next (pfile, token)
       /* See if there is another token to be pasted onto the one we just
 	 constructed.  */
       token = pasted;
-      context = CURRENT_CONTEXT (pfile);
       /* and loop */
     }
   return token;
@@ -2592,6 +2576,9 @@ push_arg_context (pfile, token)
   context->posn = 0;
   context->level = args->level;
   context->flags = CONTEXT_ARG | CONTEXT_RAW;
+  if ((context[-1].u.list->flags & VAR_ARGS)
+      && token->val.aux + 1 == (unsigned) context[-1].u.list->paramc)
+    context->flags |= CONTEXT_VARARGS;
   context->pushed_token = 0;
 
   /* Set the flags of the first token.  There is one.  */
diff --git a/gcc/cpplib.h b/gcc/cpplib.h
index 9b12713..0f52352 100644
--- a/gcc/cpplib.h
+++ b/gcc/cpplib.h
@@ -160,7 +160,6 @@ struct cpp_string
 #define PASTE_LEFT	(1 << 4) /* If on LHS of a ## operator.  */
 #define PASTED		(1 << 5) /* The result of a ## operator.  */
 #define NAMED_OP	(1 << 6) /* C++ named operators, also "defined".  */
-#define VOID_REST	(1 << 7) /* When a rest arg gets zero actual args.  */
 
 /* A preprocessing token.  This has been carefully packed and should
    occupy 16 bytes on 32-bit hosts and 24 bytes on 64-bit hosts.  */
diff --git a/gcc/testsuite/gcc.dg/cpp/vararg1.c b/gcc/testsuite/gcc.dg/cpp/vararg1.c
index aa8ed79..38bf56b 100644
--- a/gcc/testsuite/gcc.dg/cpp/vararg1.c
+++ b/gcc/testsuite/gcc.dg/cpp/vararg1.c
@@ -1,11 +1,19 @@
+/* { dg-do run } */
+/* { dg-options -w } */
+
+/* count() used to give 1 owing to a buggy test for varargs.  */
+#define count(y...)  count1 ( , ##y)
+#define count1(y...) count2 (y,1,0)
+#define count2(_,x0,n,y...) n
+#if count() != 0 || count(A) != 1
+#error Incorrect vararg argument counts
+#endif
+
 /* Test for changed behavior of the GNU varargs extension.
    ##args, where args is a rest argument which received zero tokens,
    used to delete the previous sequence of nonwhitespace characters.
    Now it deletes the previous token.  */
 
-/* { dg-do run } */
-/* { dg-options -w } */
-
 #include <string.h>
 
 #define S(str, args...) "  " str "\n", ##args
@@ -16,4 +24,3 @@ main()
   const char *s = S("foo");
   return strchr (s, '\n') == NULL;
 }
-