Commit 101b29a2 authored by Johannes Berg's avatar Johannes Berg Committed by Linus Torvalds

byteswap: don't use __builtin_bswap*() with sparse

Although sparse declares __builtin_bswap*(), it can't actually do
constant folding inside them (yet).  As such, things like

  switch (protocol) {
  case htons(ETH_P_IP):
          break;
  }

which we do all over the place cause sparse to warn that it expects a
constant instead of a function call.

Disable __HAVE_BUILTIN_BSWAP*__ if __CHECKER__ is defined to avoid this.

Fixes: 7322dd75 ("byteswap: try to avoid __builtin_constant_p gcc bug")
Link: http://lkml.kernel.org/r/1470914102-26389-1-git-send-email-johannes@sipsolutions.netSigned-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 61c04572
...@@ -242,7 +242,11 @@ ...@@ -242,7 +242,11 @@
*/ */
#define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0) #define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0)
#ifdef CONFIG_ARCH_USE_BUILTIN_BSWAP /*
* sparse (__CHECKER__) pretends to be gcc, but can't do constant
* folding in __builtin_bswap*() (yet), so don't set these for it.
*/
#if defined(CONFIG_ARCH_USE_BUILTIN_BSWAP) && !defined(__CHECKER__)
#if GCC_VERSION >= 40400 #if GCC_VERSION >= 40400
#define __HAVE_BUILTIN_BSWAP32__ #define __HAVE_BUILTIN_BSWAP32__
#define __HAVE_BUILTIN_BSWAP64__ #define __HAVE_BUILTIN_BSWAP64__
...@@ -250,7 +254,7 @@ ...@@ -250,7 +254,7 @@
#if GCC_VERSION >= 40800 #if GCC_VERSION >= 40800
#define __HAVE_BUILTIN_BSWAP16__ #define __HAVE_BUILTIN_BSWAP16__
#endif #endif
#endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP */ #endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP && !__CHECKER__ */
#if GCC_VERSION >= 50000 #if GCC_VERSION >= 50000
#define KASAN_ABI_VERSION 4 #define KASAN_ABI_VERSION 4
......
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