From: Dave Hansen Date: Wed, 25 May 2011 00:11:41 +0000 (-0700) Subject: include/linux/gfp.h: work around apparent sparse confusion X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=15fa8f425557a0d698f933627771f520ef4ae34b;p=openwrt%2Fstaging%2Fblogic.git include/linux/gfp.h: work around apparent sparse confusion Running sparse on page_alloc.c today, it errors out: include/linux/gfp.h:254:17: error: bad constant expression include/linux/gfp.h:254:17: error: cannot size expression which is a line in gfp_zone(): BUILD_BUG_ON((GFP_ZONE_BAD >> bit) & 1); That's really unfortunate, because it ends up hiding all of the other legitimate sparse messages like this: mm/page_alloc.c:5315:59: warning: incorrect type in argument 1 (different base types) mm/page_alloc.c:5315:59: expected unsigned long [unsigned] [usertype] size mm/page_alloc.c:5315:59: got restricted gfp_t [usertype] ... Having sparse be able to catch these very oopsable bugs is a lot more important than keeping a BUILD_BUG_ON(). Kill the BUILD_BUG_ON(). Compiles on x86_64 with and without CONFIG_DEBUG_VM=y. defconfig boots fine for me. Signed-off-by: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/include/linux/gfp.h b/include/linux/gfp.h index 56d8fc87fbbc..7e8f5d863c76 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -249,14 +249,9 @@ static inline enum zone_type gfp_zone(gfp_t flags) z = (GFP_ZONE_TABLE >> (bit * ZONES_SHIFT)) & ((1 << ZONES_SHIFT) - 1); - - if (__builtin_constant_p(bit)) - BUILD_BUG_ON((GFP_ZONE_BAD >> bit) & 1); - else { #ifdef CONFIG_DEBUG_VM - BUG_ON((GFP_ZONE_BAD >> bit) & 1); + BUG_ON((GFP_ZONE_BAD >> bit) & 1); #endif - } return z; }