[C++ Patch] PR 54526 (again)

[Paolo Carlini]

Hi,

On 01/03/2013 10:56 PM, Jason Merrill wrote:
> On 01/03/2013 05:44 AM, Paolo Carlini wrote:
>> +          /* C++11 - 2.5 p3, bullet 2. */
>
> Please flesh out this comment some more.
Ok, I extended it like this.

Thanks,
Paolo.

/////////////////////
-------------- next part --------------
Index: gcc/cp/parser.c
===================================================================
--- gcc/cp/parser.c	(revision 194884)
+++ gcc/cp/parser.c	(working copy)
@@ -1,6 +1,6 @@
 /* C++ Parser.
    Copyright (C) 2000, 2001, 2002, 2003, 2004,
-   2005, 2007, 2008, 2009, 2010, 2011, 2012  Free Software Foundation, Inc.
+   2005, 2007-2013  Free Software Foundation, Inc.
    Written by Mark Mitchell <mark@codesourcery.com>.
 
    This file is part of GCC.
@@ -12655,11 +12655,9 @@ cp_parser_template_id (cp_parser *parser,
 	  return error_mark_node;
 	}
       /* Otherwise, emit an error about the invalid digraph, but continue
-	 parsing because we got our argument list.  In C++11 do not emit
-	 any error, per 2.5/3.  */
-      if (cxx_dialect < cxx0x
-	  && permerror (next_token->location,
-			"%<<::%> cannot begin a template-argument list"))
+	 parsing because we got our argument list.  */
+      if (permerror (next_token->location,
+		     "%<<::%> cannot begin a template-argument list"))
 	{
 	  static bool hint = false;
 	  inform (next_token->location,
Index: gcc/testsuite/g++.dg/cpp0x/parse2.C
===================================================================
--- gcc/testsuite/g++.dg/cpp0x/parse2.C	(revision 194884)
+++ gcc/testsuite/g++.dg/cpp0x/parse2.C	(working copy)
@@ -10,3 +10,6 @@ int main()
 {
   X<::A> x;
 }
+
+int a;
+bool b = 0<::a;
Index: gcc/testsuite/g++.old-deja/g++.other/crash28.C
===================================================================
--- gcc/testsuite/g++.old-deja/g++.other/crash28.C	(revision 194884)
+++ gcc/testsuite/g++.old-deja/g++.other/crash28.C	(working copy)
@@ -31,5 +31,5 @@ class foo
 };
 void foo::x() throw(bar)
 {
-  if (!b) throw bar (static_cast<::N::X*>(this));	// { dg-error "lambda expressions|expected" } parse error
+  if (!b) throw bar (static_cast<::N::X*>(this));	// { dg-error "lambda expressions|expected|invalid" } parse error
 }
Index: libcpp/lex.c
===================================================================
--- libcpp/lex.c	(revision 194884)
+++ libcpp/lex.c	(working copy)
@@ -1,6 +1,6 @@
 /* CPP Library - lexical analysis.
-   Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010,
-   2011, 2012 Free Software Foundation, Inc.
+   Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2007-2013
+   Free Software Foundation, Inc.
    Contributed by Per Bothner, 1994-95.
    Based on CCCP program by Paul Rubin, June 1986
    Adapted to ANSI C, Richard Stallman, Jan 1987
@@ -2290,6 +2290,17 @@ _cpp_lex_direct (cpp_reader *pfile)
 	{
 	  if (*buffer->cur == ':')
 	    {
+	      /* C++11 [2.5/3 lex.pptoken], "Otherwise, if the next
+		 three characters are <:: and the subsequent character
+		 is neither : nor >, the < is treated as a preprocessor
+		 token by itself".  */
+	      if (CPP_OPTION (pfile, cplusplus)
+		  && (CPP_OPTION (pfile, lang) == CLK_CXX11
+		      || CPP_OPTION (pfile, lang) == CLK_GNUCXX11)
+		  && buffer->cur[1] == ':'
+		  && buffer->cur[2] != ':' && buffer->cur[2] != '>')
+		break;
+
 	      buffer->cur++;
 	      result->flags |= DIGRAPH;
 	      result->type = CPP_OPEN_SQUARE;