Commit-ID: bdfc017eead9bc17cd23317ff42eb7297cb9468a Gitweb: http://git.kernel.org/tip/bdfc017eead9bc17cd23317ff42eb7297cb9468a Author: Jan-Simon Möller <[email protected]> AuthorDate: Thu, 29 Aug 2013 21:13:05 +0200 Committer: H. Peter Anvin <[email protected]> CommitDate: Thu, 29 Aug 2013 13:26:33 -0700
x86, asm: Fix a compilation issue with clang Clang does not support the "shortcut" we're taking here for gcc (see below). The patch uses the macro _ASM_DX to do the job. >From arch/x86/include/asm/uaccess.h: /* * Careful: we have to cast the result to the type of the pointer * for sign reasons. * * The use of %edx as the register specifier is a bit of a * simplification, as gcc only cares about it as the starting point * and not size: for a 64-bit value it will use %ecx:%edx on 32 bits * (%ecx being the next register in gcc's x86 register sequence), and * %rdx on 64 bits. */ [ hpa: I consider this a compatibility bug in clang as this reflects a bit of a misunderstanding about how register strings are used by gcc, but the workaround is straightforward and there is no particular reason to not do it. ] Signed-off-by: Jan-Simon Möller <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: H. Peter Anvin <[email protected]> --- arch/x86/include/asm/uaccess.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index 5ee2687..f715fee 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -162,7 +162,7 @@ __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL)) #define get_user(x, ptr) \ ({ \ int __ret_gu; \ - register __inttype(*(ptr)) __val_gu asm("%edx"); \ + register __inttype(*(ptr)) __val_gu asm("%"_ASM_DX); \ __chk_user_ptr(ptr); \ might_fault(); \ asm volatile("call __get_user_%P3" \ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
