Re: [PATCH 2/3] Add DIAGNOSTIC_IGNORE_STRINGOP_TRUNCATION

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Fri, Jun 1, 2018 at 3:19 AM, Alan Modra <amodra@gmail.com> wrote:
> On Fri, Jun 01, 2018 at 08:57:20AM +0100, Nick Clifton wrote:
>> Hi H.J.
>>
>> > +# if __GNUC__ >= 8
>> > +#  define DIAGNOSTIC_IGNORE_STRINGOP_TRUNCATION \
>> > +  DIAGNOSTIC_IGNORE ("-Wstringop-truncation")
>> > +# endif
>> > +#endif
>>
>> Presumably the Wstringop-truncation bug will be fixed in gcc 8.1
>> so shouldn't the test check the revision number as well ?
>
> Yes, it has already been fixed.
>

The bug is in GCC 8.1 and will be fixed in GCC 8.2.  Here is the
updated patch with

+# if __GNUC__ == 8 && __GNUC_MINOR__ < 2
+#  define DIAGNOSTIC_IGNORE_STRINGOP_TRUNCATION \
+  DIAGNOSTIC_IGNORE ("-Wstringop-truncation")
+# endif

OK for master?

-- 
H.J.

From bb1d3ddd78abf25b30e11cf25e4b2ec7b6ef0688 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Mon, 21 May 2018 05:06:39 -0700
Subject: [PATCH 1/2] Add DIAGNOSTIC_IGNORE_STRINGOP_TRUNCATION

Add DIAGNOSTIC_IGNORE_STRINGOP_TRUNCATION for GCC 8.1 to silence
-Wstringop-truncation warning:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85643

	* diagnostics.h (DIAGNOSTIC_STRINGIFY_1): New.
	(DIAGNOSTIC_STRINGIFY): Likewise.
	(DIAGNOSTIC_IGNORE): Replace STRINGIFY with DIAGNOSTIC_STRINGIFY.
	(DIAGNOSTIC_IGNORE_SELF_MOVE): Define empty if not defined.
	(DIAGNOSTIC_IGNORE_DEPRECATED_REGISTER): Likewise.
	(DIAGNOSTIC_IGNORE_UNUSED_FUNCTION): Likewise.
	(DIAGNOSTIC_IGNORE_SWITCH_DIFFERENT_ENUM_TYPES): Likewise.
	(DIAGNOSTIC_IGNORE_STRINGOP_TRUNCATION): New.
---
 include/diagnostics.h | 31 ++++++++++++++++++++++++-------
 1 file changed, 24 insertions(+), 7 deletions(-)

diff --git a/include/diagnostics.h b/include/diagnostics.h
index 0725664177..f7412d4a38 100644
--- a/include/diagnostics.h
+++ b/include/diagnostics.h
@@ -19,8 +19,13 @@
 #ifdef __GNUC__
 # define DIAGNOSTIC_PUSH _Pragma ("GCC diagnostic push")
 # define DIAGNOSTIC_POP _Pragma ("GCC diagnostic pop")
+
+/* Stringification.  */
+# define DIAGNOSTIC_STRINGIFY_1(x) #x
+# define DIAGNOSTIC_STRINGIFY(x) DIAGNOSTIC_STRINGIFY_1 (x)
+
 # define DIAGNOSTIC_IGNORE(option) \
-  _Pragma (STRINGIFY (GCC diagnostic ignored option))
+  _Pragma (DIAGNOSTIC_STRINGIFY (GCC diagnostic ignored option))
 #else
 # define DIAGNOSTIC_PUSH
 # define DIAGNOSTIC_POP
@@ -37,24 +42,36 @@
 # if __has_warning ("-Wenum-compare-switch")
 #  define DIAGNOSTIC_IGNORE_SWITCH_DIFFERENT_ENUM_TYPES \
    DIAGNOSTIC_IGNORE ("-Wenum-compare-switch")
-# else
-#  define DIAGNOSTIC_IGNORE_SWITCH_DIFFERENT_ENUM_TYPES
 # endif
 #elif defined (__GNUC__) /* GCC */
 
-# define DIAGNOSTIC_IGNORE_SELF_MOVE
-# define DIAGNOSTIC_IGNORE_DEPRECATED_REGISTER
 # define DIAGNOSTIC_IGNORE_UNUSED_FUNCTION \
   DIAGNOSTIC_IGNORE ("-Wunused-function")
-# define DIAGNOSTIC_IGNORE_SWITCH_DIFFERENT_ENUM_TYPES
 
-#else /* Other compilers */
+# if __GNUC__ == 8 && __GNUC_MINOR__ < 2
+#  define DIAGNOSTIC_IGNORE_STRINGOP_TRUNCATION \
+  DIAGNOSTIC_IGNORE ("-Wstringop-truncation")
+# endif
+#endif
 
+#ifndef DIAGNOSTIC_IGNORE_SELF_MOVE
 # define DIAGNOSTIC_IGNORE_SELF_MOVE
+#endif
+
+#ifndef DIAGNOSTIC_IGNORE_DEPRECATED_REGISTER
 # define DIAGNOSTIC_IGNORE_DEPRECATED_REGISTER
+#endif
+
+#ifndef DIAGNOSTIC_IGNORE_UNUSED_FUNCTION
 # define DIAGNOSTIC_IGNORE_UNUSED_FUNCTION
+#endif
+
+#ifndef DIAGNOSTIC_IGNORE_SWITCH_DIFFERENT_ENUM_TYPES
 # define DIAGNOSTIC_IGNORE_SWITCH_DIFFERENT_ENUM_TYPES
+#endif
 
+#ifndef DIAGNOSTIC_IGNORE_STRINGOP_TRUNCATION
+# define DIAGNOSTIC_IGNORE_STRINGOP_TRUNCATION
 #endif
 
 #endif /* DIAGNOSTICS_H */
-- 
2.17.0