[RFC PATCH] Stringify support commas v2

[RFC PATCH] Stringify support commas v2

[Mathieu Desnoyers]

#define MYDEF a, b, c

__stringify(MYDEF) should be replaced by "a, b, c", but compilation fails
because the __stringify macro expects only one argument. Fix it by using
variable macro arguments in __stringify and __stringify_1.

Needed in my current NMI safe iret paravirt support work so I can expand
a macro containing assembly code into a string.

Since some architectures still use -traditional, which does not support macros
with variable arguments, keep the old stringify around. Test with __STDC__ to
see if -traditional is used.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
CC: akpm@osdl.org
CC: Sam Ravnborg <sam@ravnborg.org>
---
 include/linux/stringify.h |    5 +++++
 1 file changed, 5 insertions(+)

Index: linux-2.6-lttng/include/linux/stringify.h
===================================================================
--- linux-2.6-lttng.orig/include/linux/stringify.h	2008-04-22 14:16:21.000000000 -0400
+++ linux-2.6-lttng/include/linux/stringify.h	2008-04-22 14:19:26.000000000 -0400
@@ -6,7 +6,12 @@
  * converts to "bar".
  */
 
+#ifdef __STDC__
+#define __stringify_1(x...)	#x
+#define __stringify(x...)	__stringify_1(x)
+#else	/* Support gcc -traditional, without commas. */
 #define __stringify_1(x)	#x
 #define __stringify(x)		__stringify_1(x)
+#endif
 
 #endif	/* !__LINUX_STRINGIFY_H */

-- 
Mathieu Desnoyers
Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE 9A68