runtime: fix arm build

TBR=minux
CC=golang-codereviews
https://golang.org/cl/137810043

diff --git a/src/pkg/runtime/asm_arm.s b/src/pkg/runtime/asm_arm.s
index 93eb08d84bbb11c158e143b0bba963b466ab0e20..f7b90a692e471ed5a1a8fbfe8195188dfe574148 100644 (file)
--- a/src/pkg/runtime/asm_arm.s
+++ b/src/pkg/runtime/asm_arm.s
@@ -691,7 +691,7 @@ casfail:
        RET
 
 TEXT runtime·casuintptr(SB), NOSPLIT, $0-13
-       JMP     runtime·cas(SB)
+       B       runtime·cas(SB)
 
 TEXT runtime·stackguard(SB),NOSPLIT,$0-8
        MOVW    R13, R1