[PATCH 04/20] x86: avoid unneeded __div64_32 function definition

From: Arnd Bergmann
Date: Tue May 16 2023 - 15:36:51 EST


From: Arnd Bergmann <arnd@xxxxxxxx>

The __div64_32() function is provided for 32-bit architectures that
don't have a custom do_div() implementation. x86_32 has one, and
does not use the header file that declares the function prototype,
so the definition causes a W=1 warning:

lib/math/div64.c:31:32: error: no previous prototype for '__div64_32' [-Werror=missing-prototypes]

Define an empty macro to prevent the function definition from getting
built, which avoids the warning and saves a little .text space.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
arch/x86/include/asm/div64.h | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/x86/include/asm/div64.h b/arch/x86/include/asm/div64.h
index b8f1dc0761e4..9826d5fc12e3 100644
--- a/arch/x86/include/asm/div64.h
+++ b/arch/x86/include/asm/div64.h
@@ -71,6 +71,8 @@ static inline u64 mul_u32_u32(u32 a, u32 b)
}
#define mul_u32_u32 mul_u32_u32

+#define __div64_32 /* not needed */
+
#else
# include <asm-generic/div64.h>

--
2.39.2