From 8d4fbcfbe0a4bfc73e7f0297c59ae514e1f1436f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 31 Jul 2007 21:12:07 -0700 Subject: Fix WARN_ON() on bitfield ops Alexey Dobriyan noticed that the new WARN_ON() semantics that were introduced by commit 684f978347deb42d180373ac4c427f82ef963171 (to also return the value to be warned on) didn't compile when given a bitfield, because the typeof doesn't work for bitfields. So instead of the typeof trick, use an "int" variable together with a "!!(x)" expression, as suggested by Al Viro. To make matters more interesting, Paul Mackerras points out that that is sub-optimal on Power, but the old asm-coded comparison seems to be buggy anyway on 32-bit Power if the conditional was 64-bit, so I think there are more problems there. Regardless, the new WARN_ON() semantics may have been a bad idea. But this at least avoids the more serious complications. Cc: Alexey Dobriyan Cc: Herbert Xu Cc: Paul Mackerras Cc: Al Viro Cc: Ingo Molnar Cc: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-powerpc/bug.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/asm-powerpc/bug.h') diff --git a/include/asm-powerpc/bug.h b/include/asm-powerpc/bug.h index a248b8bd4d7..e55d1f66b86 100644 --- a/include/asm-powerpc/bug.h +++ b/include/asm-powerpc/bug.h @@ -93,7 +93,7 @@ } while (0) #define WARN_ON(x) ({ \ - typeof(x) __ret_warn_on = (x); \ + int __ret_warn_on = !!(x); \ if (__builtin_constant_p(__ret_warn_on)) { \ if (__ret_warn_on) \ __WARN(); \ -- cgit v1.2.3