diff mbox

[C++] PR 50810 (new try)

Message ID 4EA55BC2.2090700@oracle.com
State New
Headers show

Commit Message

Paolo Carlini Oct. 24, 2011, 12:36 p.m. UTC
On 10/24/2011 02:18 PM, Paolo Carlini wrote:
>> OK with a minor correction.  This bit
>>
>> +With -std=c++0x, @option{-Wno-c++0x-compat} can be used to suppress
>> +the diagnostic required by the standard.
>>
>> should not be there.  It is currently an accident of implementation
>> detail as opposed to a feature.  It needs no advertisement.
>
> Ok. But I actively made it possible, if you want I can remove the 
> possibility altogether, the patch also becomes cleaner ;)
I can boot & test the below, in other terms.

Paolo.

////////////////////////
/c-family
2011-10-24  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/50810
	* c-opts.c (c_common_handle_option): Do not enable -Wc++0x-compat
	as part of -Wall; handle -Wc++0x-compat.
	(c_common_post_options): -std=c++0x enables -Wnarrowing.
	* c.opt ([Wnarrowing]): Update.

/cp
2011-10-24  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/50810
	* typeck2.c (check_narrowing): Adjust OPT_Wnarrowing diagnostics.
	(digest_init_r): Call check_narrowing irrespective of the C++ dialect.
	* decl.c (check_initializer): Likewise.
	* semantics.c (finish_compound_literal): Likewise.

/testsuite
2011-10-24  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/50810
	* g++.dg/cpp0x/warn_cxx0x2.C: New.
	* g++.dg/cpp0x/warn_cxx0x3.C: Likewise.
	* g++.dg/cpp0x/initlist55.C: Adjust.

2011-10-24  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/50810
	* doc/invoke.texi ([-Wall], [-Wnarrowing], [-Wc++0x-compat]): Update.
diff mbox

Patch

Index: doc/invoke.texi
===================================================================
--- doc/invoke.texi	(revision 180373)
+++ doc/invoke.texi	(working copy)
@@ -2365,17 +2365,16 @@  an instance of a derived class through a pointer t
 base class does not have a virtual destructor.  This warning is enabled
 by @option{-Wall}.
 
-@item -Wno-narrowing @r{(C++ and Objective-C++ only)}
+@item -Wnarrowing @r{(C++ and Objective-C++ only)}
 @opindex Wnarrowing
 @opindex Wno-narrowing
-With -std=c++0x, suppress the diagnostic required by the standard for
-narrowing conversions within @samp{@{ @}}, e.g.
+Warn when a narrowing conversion occurs within @samp{@{ @}}, e.g.
 
 @smallexample
 int i = @{ 2.2 @}; // error: narrowing from double to int
 @end smallexample
 
-This flag can be useful for compiling valid C++98 code in C++0x mode
+This flag is included in @option{-Wc++0x-compat}.
 
 @item -Wnoexcept @r{(C++ and Objective-C++ only)}
 @opindex Wnoexcept
@@ -2993,7 +2992,6 @@  Options} and @ref{Objective-C and Objective-C++ Di
 
 @gccoptlist{-Waddress   @gol
 -Warray-bounds @r{(only with} @option{-O2}@r{)}  @gol
--Wc++0x-compat  @gol
 -Wchar-subscripts  @gol
 -Wenum-compare @r{(in C/Objc; this is on by default in C++)} @gol
 -Wimplicit-int @r{(C and Objective-C only)} @gol
@@ -4066,7 +4064,7 @@  ISO C and ISO C++, e.g.@: request for implicit con
 @item -Wc++0x-compat @r{(C++ and Objective-C++ only)}
 Warn about C++ constructs whose meaning differs between ISO C++ 1998 and
 ISO C++ 200x, e.g., identifiers in ISO C++ 1998 that will become keywords
-in ISO C++ 200x.  This warning is enabled by @option{-Wall}.
+in ISO C++ 200x.  This warning turns on @option{-Wnarrowing}.
 
 @item -Wcast-qual
 @opindex Wcast-qual
Index: c-family/c.opt
===================================================================
--- c-family/c.opt	(revision 180373)
+++ c-family/c.opt	(working copy)
@@ -490,8 +490,8 @@  C ObjC C++ ObjC++ Warning
 Warn about use of multi-character character constants
 
 Wnarrowing
-C ObjC C++ ObjC++ Warning Var(warn_narrowing) Init(1)
--Wno-narrowing	  In C++0x mode, ignore ill-formed narrowing conversions within { }
+C ObjC C++ ObjC++ Warning Var(warn_narrowing) Init(-1) Warning
+Warn about ill-formed narrowing conversions within { }
 
 Wnested-externs
 C ObjC Var(warn_nested_externs) Warning
Index: c-family/c-opts.c
===================================================================
--- c-family/c-opts.c	(revision 180373)
+++ c-family/c-opts.c	(working copy)
@@ -404,7 +404,6 @@  c_common_handle_option (size_t scode, const char *
 	  /* C++-specific warnings.  */
           warn_sign_compare = value;
 	  warn_reorder = value;
-          warn_cxx0x_compat = value;
           warn_delnonvdtor = value;
 	}
 
@@ -436,6 +435,10 @@  c_common_handle_option (size_t scode, const char *
       cpp_opts->warn_cxx_operator_names = value;
       break;
 
+    case OPT_Wc__0x_compat:
+      warn_narrowing = value;
+      break;
+
     case OPT_Wdeprecated:
       cpp_opts->cpp_warn_deprecated = value;
       break;
@@ -997,10 +1000,15 @@  c_common_post_options (const char **pfilename)
   if (warn_implicit_function_declaration == -1)
     warn_implicit_function_declaration = flag_isoc99;
 
-  /* If we're allowing C++0x constructs, don't warn about C++0x
-     compatibility problems.  */
   if (cxx_dialect == cxx0x)
-    warn_cxx0x_compat = 0;
+    {
+      /* If we're allowing C++0x constructs, don't warn about C++98
+	 identifiers which are keywords in C++0x.  */
+      warn_cxx0x_compat = 0;
+      warn_narrowing = 1;
+    }
+  else if (warn_narrowing == -1)
+    warn_narrowing = 0;
 
   if (flag_preprocess_only)
     {
Index: testsuite/g++.dg/cpp0x/warn_cxx0x2.C
===================================================================
--- testsuite/g++.dg/cpp0x/warn_cxx0x2.C	(revision 0)
+++ testsuite/g++.dg/cpp0x/warn_cxx0x2.C	(revision 0)
@@ -0,0 +1,5 @@ 
+// PR c++/50810
+// { dg-options "-std=gnu++98 -Wc++0x-compat" }
+
+int i;
+float data[] = { i }; // { dg-warning "narrowing" }
Index: testsuite/g++.dg/cpp0x/warn_cxx0x3.C
===================================================================
--- testsuite/g++.dg/cpp0x/warn_cxx0x3.C	(revision 0)
+++ testsuite/g++.dg/cpp0x/warn_cxx0x3.C	(revision 0)
@@ -0,0 +1,5 @@ 
+// PR c++/50810
+// { dg-options "-std=gnu++98 -Wc++0x-compat -Wno-narrowing" }
+
+int i;
+float data[] = { i };
Index: testsuite/g++.dg/cpp0x/initlist55.C
===================================================================
--- testsuite/g++.dg/cpp0x/initlist55.C	(revision 180373)
+++ testsuite/g++.dg/cpp0x/initlist55.C	(working copy)
@@ -2,4 +2,4 @@ 
 // { dg-options "-std=c++0x -pedantic-errors -Wno-narrowing" }
 
 int i;
-float d = { i };
+float d = { i }; // { dg-error "narrowing" }
Index: cp/decl.c
===================================================================
--- cp/decl.c	(revision 180373)
+++ cp/decl.c	(working copy)
@@ -5523,7 +5523,7 @@  check_initializer (tree decl, tree init, int flags
 	  else
 	    {
 	      init = reshape_init (type, init, tf_warning_or_error);
-	      if (cxx_dialect >= cxx0x && SCALAR_TYPE_P (type))
+	      if (SCALAR_TYPE_P (type))
 		check_narrowing (type, init);
 	    }
 	}
Index: cp/typeck2.c
===================================================================
--- cp/typeck2.c	(revision 180373)
+++ cp/typeck2.c	(working copy)
@@ -803,8 +803,10 @@  check_narrowing (tree type, tree init)
     }
 
   if (!ok)
-    pedwarn (input_location, OPT_Wnarrowing, "narrowing conversion of %qE "
-	     "from %qT to %qT inside { }", init, ftype, type);
+    emit_diagnostic ((cxx_dialect != cxx98) ? DK_PEDWARN : DK_WARNING,
+		     input_location, OPT_Wnarrowing,
+		     "narrowing conversion of %qE from %qT to %qT inside { }",
+		     init, ftype, type);
 }
 
 /* Process the initializer INIT for a variable of type TYPE, emitting
@@ -901,7 +903,7 @@  digest_init_r (tree type, tree init, bool nested,
     {
       tree *exp;
 
-      if (cxx_dialect != cxx98 && nested)
+      if (nested)
 	check_narrowing (type, init);
       init = convert_for_initialization (0, type, init, flags,
 					 ICR_INIT, NULL_TREE, 0,
Index: cp/semantics.c
===================================================================
--- cp/semantics.c	(revision 180373)
+++ cp/semantics.c	(working copy)
@@ -2369,7 +2369,7 @@  finish_compound_literal (tree type, tree compound_
       && check_array_initializer (NULL_TREE, type, compound_literal))
     return error_mark_node;
   compound_literal = reshape_init (type, compound_literal, complain);
-  if (cxx_dialect >= cxx0x && SCALAR_TYPE_P (type)
+  if (SCALAR_TYPE_P (type)
       && !BRACE_ENCLOSED_INITIALIZER_P (compound_literal))
     check_narrowing (type, compound_literal);
   if (TREE_CODE (type) == ARRAY_TYPE