src/runtime/sys_darwin_386.s   | 5 +++++
 src/runtime/sys_darwin_amd64.s | 7 ++++++-

diff --git a/src/runtime/sys_darwin_386.s b/src/runtime/sys_darwin_386.s
index 9e45f8a0024651e50777d707a93be9fcb469e605..83f4709f385fbfdb0611c26ae2bb02667b742a19 100644
--- a/src/runtime/sys_darwin_386.s
+++ b/src/runtime/sys_darwin_386.s
@@ -201,6 +201,11 @@ 	MOVL	AX, 4(SP)
 	MOVL	$0, 8(SP)	// time zone pointer
 	MOVL	$116, AX
 	INT	$0x80
+	CMPL	AX, $0
+	JNE	inreg
+	MOVL	12(SP), AX
+	MOVL	16(SP), DX
+inreg:
 	// sec is in AX, usec in DX
 	// convert to DX:AX nsec
 	MOVL	DX, BX
diff --git a/src/runtime/sys_darwin_amd64.s b/src/runtime/sys_darwin_amd64.s
index 7b9cf6a3bcdc2570b38d2444a93fa5a898d8daf0..e09b906ba571f227308773ac40c87e6e0ec603f7 100644
--- a/src/runtime/sys_darwin_amd64.s
+++ b/src/runtime/sys_darwin_amd64.s
@@ -155,10 +155,15 @@ 	RET
 
 systime:
 	// Fall back to system call (usually first call in this thread).
-	MOVQ	SP, DI	// must be non-nil, unused
+	MOVQ	SP, DI
 	MOVQ	$0, SI
 	MOVL	$(0x2000000+116), AX
 	SYSCALL
+	CMPQ	AX, $0
+	JNE	inreg
+	MOVQ	0(SP), AX
+	MOVL	8(SP), DX
+inreg:
 	// sec is in AX, usec in DX
 	// return nsec in AX
 	IMULQ	$1000000000, AX