[PATCH] Add option -Wno-mudflap to silence warning triggered by -fmudflap

[Volker Reichelt]

Right now the only way to disable warnings triggered by -fmudflap is to use
the flag "-w". The following patch adds the option -Wno-mudflap to silence
these warnings and documents it.

Bootstrapped and regtested on i686-pc-linux-gnu.
Ok for mainline?

Regards,
Volker

:ADDPATCH mudflap:


2008-01-21  Volker Reichelt  <v.reichelt@netcologne.de>

	* common.opt (Wmudflap): New option.
	* tree-mudflap.c (mf_xform_derefs_1): Guard warning by OPT_Wmudflap.
	(mx_register_decls): Likewise.
	(mudflap_finish_file): Likewise.
	* doc/invoke.texi: Document -Wno-mudflap.

===================================================================
--- gcc/common.opt	(revision 131273)
+++ gcc/common.opt	(working copy)
@@ -129,6 +129,10 @@
 Common Var(warn_missing_noreturn) Warning
 Warn about functions which might be candidates for __attribute__((noreturn))
 
+Wmudflap
+Common Var(warn_mudflap) Init(1) Warning
+Warn about constructs not instrumented by -fmudflap
+
 Woverflow
 Common Var(warn_overflow) Init(1) Warning
 Warn about overflow in arithmetic expressions
===================================================================
--- gcc/tree-mudflap.c	(revision 131273)
+++ gcc/tree-mudflap.c	(working copy)
@@ -861,7 +861,8 @@
       break;
 
     case ARRAY_RANGE_REF:
-      warning (0, "mudflap checking not yet implemented for ARRAY_RANGE_REF");
+      warning (OPT_Wmudflap,
+	       "mudflap checking not yet implemented for ARRAY_RANGE_REF");
       return;
 
     case BIT_FIELD_REF:
@@ -1047,7 +1048,8 @@
           if (tsi_end_p (initially_stmts))
 	    {
 	      if (!DECL_ARTIFICIAL (decl))
-		warning (0, "mudflap cannot track %qs in stub function",
+		warning (OPT_Wmudflap,
+			 "mudflap cannot track %qs in stub function",
 			 IDENTIFIER_POINTER (DECL_NAME (decl)));
 	    }
 	  else
@@ -1276,7 +1278,8 @@
 
           if (! COMPLETE_TYPE_P (TREE_TYPE (obj)))
             {
-              warning (0, "mudflap cannot track unknown size extern %qs",
+              warning (OPT_Wmudflap,
+		       "mudflap cannot track unknown size extern %qs",
                        IDENTIFIER_POINTER (DECL_NAME (obj)));
               continue;
             }
===================================================================
--- gcc/doc/invoke.texi	2008-01-19 22:00:04 +0100
+++ gcc/doc/invoke.texi	2008-01-20 21:18:07 +0100
@@ -244,7 +244,7 @@ Objective-C and Objective-C++ Dialects}.
 -Wlogical-op -Wlong-long @gol
 -Wmain  -Wmissing-braces  -Wmissing-field-initializers @gol
 -Wmissing-format-attribute  -Wmissing-include-dirs @gol
--Wmissing-noreturn @gol
+-Wmissing-noreturn  -Wno-mudflap @gol
 -Wno-multichar  -Wnonnull  -Wno-overflow @gol
 -Woverlength-strings  -Wpacked  -Wpadded @gol
 -Wparentheses  -Wpointer-arith  -Wno-pointer-to-int-cast @gol
@@ -3934,6 +3934,11 @@ This option is only supported for C and 
 This option is only active when @option{-fstack-protector} is active.  It
 warns about functions that will not be protected against stack smashing.
 
+@item -Wno-mudflap
+@opindex Wno-mudflap
+Suppress warnings about constructs that cannot be instrumented by
+@option{-fmudflap}.
+
 @item -Woverlength-strings
 @opindex Woverlength-strings
 Warn about string constants which are longer than the ``minimum
===================================================================

2008-01-21  Volker Reichelt  <v.reichelt@netcologne.de>

	* testsuite/libmudflap.c/pass63-frag.c: New test.

===================================================================
--- libmudflap/testsuite/libmudflap.c/pass63-frag.c	2003-09-23 19:59:22 +0200
+++ libmudflap/testsuite/libmudflap.c/pass63-frag.c	2008-01-20 21:37:24 +0100
@@ -0,0 +1,6 @@
+/* Check -Wno-mudflap flag */
+/* { dg-do compile } */
+/* { dg-options "-fmudflap -Wno-mudflap" } */
+
+extern char x[];
+int main() { return x[3]; }  /* { dg-bogus "mudflap cannot track" } */
===================================================================