buildroot

From 022ae220d6e7b5bd064bc8698c271dca4dac7d8c Mon Sep 17 00:00:00 2001

From: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

Date: Mon, 8 May 2017 22:27:25 +0200

Subject: [PATCH] x86/hyperv_clock: be explicit about mul instruction data size

​

With gcc 4.7.2, the build fails with:

​

x86/hyperv_clock.c: Assembler messages:

x86/hyperv_clock.c:21: Error: no instruction mnemonic suffix given and no register operands; can't size instruction

​

In order to avoid this, make the mul instruction data size explicit by

adding the appropriate suffix. It operates on 64-bit data, so use

"mulq".

​

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

---

 x86/hyperv_clock.c | 2 +-

 1 file changed, 1 insertion(+), 1 deletion(-)

​

diff --git a/x86/hyperv_clock.c b/x86/hyperv_clock.c

index 8b1deba..6c4dd56 100644

--- a/x86/hyperv_clock.c

+++ b/x86/hyperv_clock.c

@@ -19,7 +19,7 @@ static inline u64 scale_delta(u64 delta, u64 mul_frac)

    u64 product, unused;

    __asm__ (

-       "mul %3"

+       "mulq %3"

        : "=d" (product), "=a" (unused) : "1" (delta), "rm" ((u64)mul_frac) );

    return product;

-- 

2.7.4

​