Commit-ID: a9c640ac96e19b3966357ec9bb586edd2e1e74de Gitweb: https://git.kernel.org/tip/a9c640ac96e19b3966357ec9bb586edd2e1e74de Author: Nick Desaulniers <[email protected]> AuthorDate: Thu, 14 Mar 2019 15:14:57 -0700 Committer: Thomas Gleixner <[email protected]> CommitDate: Thu, 21 Mar 2019 12:24:38 +0100
x86/boot: Restrict header scope to make Clang happy The inclusion of <linux/kernel.h> was causing issue as the definition of __arch_hweight64 from arch/x86/include/asm/arch_hweight.h eventually gets included. The definition is problematic when compiled with -m16 (all code in arch/x86/boot/ is) as the "D" inline assembly constraint is rejected by both compilers when passed an argument of type long long (regardless of signedness, anything smaller is fine). Because GCC performs inlining before semantic analysis, and __arch_hweight64 is dead in this translation unit, GCC does not report any issues at compile time. Clang does the semantic analysis in the front end, before inlining (run in the middle) can determine the code is dead. I consider this another case of PR33587, which I think we can do more work to solve. It turns out that arch/x86/boot/string.c doesn't actually need linux/kernel.h, simply linux/limits.h and linux/compiler.h. Suggested-by: Stephen Rothwell <[email protected]> Signed-off-by: Nick Desaulniers <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Nathan Chancellor <[email protected]> Reviewed-by: Nathan Chancellor <[email protected]> Cc: [email protected] Cc: [email protected] Cc: "H. Peter Anvin" <[email protected]> Cc: Chao Fan <[email protected]> Cc: Uros Bizjak <[email protected]> Link: https://bugs.llvm.org/show_bug.cgi?id=33587 Link: https://github.com/ClangBuiltLinux/linux/issues/347 Link: https://lkml.kernel.org/r/[email protected] --- arch/x86/boot/string.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/boot/string.c b/arch/x86/boot/string.c index 315a67b8896b..90154df8f125 100644 --- a/arch/x86/boot/string.c +++ b/arch/x86/boot/string.c @@ -13,8 +13,9 @@ */ #include <linux/types.h> -#include <linux/kernel.h> +#include <linux/compiler.h> #include <linux/errno.h> +#include <linux/limits.h> #include <asm/asm.h> #include "ctype.h" #include "string.h"
