File pr27975.diff of Package gcc43

2008-05-27  Michael Matz  <matz@suse.de>
 
	PR c++/27975
	* c.opt (Wenum-compare): New warning option.
	* doc/invoke.texi  (Warning Options): Document -Wenum-compare.

	cp/
	* call.c (build_new_op): Make warning conditional on
	OPT_Wenum_compare.

	* g++.dg/warn/Wenum-compare.C: New testcase.
	* g++.dg/warn/Wenum-compare-no.C: Ditto.

Index: gcc/doc/invoke.texi
===================================================================
--- gcc/doc/invoke.texi.orig	2009-01-31 21:54:38.000000000 +0100
+++ gcc/doc/invoke.texi	2009-11-20 13:50:32.000000000 +0100
@@ -232,7 +232,7 @@ Objective-C and Objective-C++ Dialects}.
 -Wchar-subscripts -Wclobbered  -Wcomment @gol
 -Wconversion  -Wcoverage-mismatch  -Wno-deprecated-declarations @gol
 -Wdisabled-optimization  -Wno-div-by-zero  @gol
--Wempty-body  -Wno-endif-labels @gol
+-Wempty-body  -Wenum-compare  -Wno-endif-labels @gol
 -Werror  -Werror=* @gol
 -Wfatal-errors  -Wfloat-equal  -Wformat  -Wformat=2 @gol
 -Wno-format-extra-args -Wformat-nonliteral @gol
@@ -3626,6 +3626,11 @@ while} statement.  Additionally, in C++,
 in a @samp{while} or @samp{for} statement with no whitespacing before
 the semicolon.  This warning is also enabled by @option{-Wextra}.
 
+@item -Wenum-compare @r{(C++ and Objective-C++ only)}
+@opindex Wenum-compare
+@opindex Wno-enum-compare
+Warn about a comparison between values of different enum types.
+
 @item -Wsign-compare
 @opindex Wsign-compare
 @opindex Wno-sign-compare
Index: gcc/testsuite/g++.dg/warn/Wenum-compare-no.C
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ gcc/testsuite/g++.dg/warn/Wenum-compare-no.C	2009-11-20 13:50:32.000000000 +0100
@@ -0,0 +1,10 @@
+/* Test disabling -Wenum-compare (on by default).  See PR27975.  */
+/* { dg-do compile } */
+/* { dg-options "-Wno-enum-compare" } */
+enum E1 { a };
+enum E2 { b };
+
+int foo (E1 e1, E2 e2)
+{
+  return e1 == e2;  /* { dg-bogus "comparison between" } */
+}
Index: gcc/testsuite/g++.dg/warn/Wenum-compare.C
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ gcc/testsuite/g++.dg/warn/Wenum-compare.C	2009-11-20 13:50:32.000000000 +0100
@@ -0,0 +1,10 @@
+/* Test that we get the -Wenum-compare by default.  See PR27975.  */
+/* { dg-do compile } */
+/* { dg-options "" } */
+enum E1 { a };
+enum E2 { b };
+
+int foo (E1 e1, E2 e2)
+{
+  return e1 == e2;  /* { dg-warning "comparison between" } */
+}
Index: gcc/cp/call.c
===================================================================
--- gcc/cp/call.c.orig	2009-06-17 13:58:55.000000000 +0200
+++ gcc/cp/call.c	2009-11-20 13:50:32.000000000 +0100
@@ -3975,7 +3975,8 @@ build_new_op (enum tree_code code, int f
 		  && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
 		      != TYPE_MAIN_VARIANT (TREE_TYPE (arg2))))
 		{
-		  warning (0, "comparison between %q#T and %q#T",
+		  warning (OPT_Wenum_compare,
+			   "comparison between %q#T and %q#T",
 			   TREE_TYPE (arg1), TREE_TYPE (arg2));
 		}
 	      break;
Index: gcc/c.opt
===================================================================
--- gcc/c.opt.orig	2009-11-20 13:50:25.000000000 +0100
+++ gcc/c.opt	2009-11-20 13:50:32.000000000 +0100
@@ -199,6 +199,10 @@ Wendif-labels
 C ObjC C++ ObjC++ Warning
 Warn about stray tokens after #elif and #endif
 
+Wenum-compare
+C++ ObjC++ Var(warn_enum_compare) Init(1) Warning
+Warn about comparison of different enum types
+
 Werror
 C ObjC C++ ObjC++
 ; Documented in common.opt