diff --git a/src/runtime/sys_darwin_386.s b/src/runtime/sys_darwin_386.s
index 5c62bfd20e..dc4516dbdd 100644
--- a/src/runtime/sys_darwin_386.s
+++ b/src/runtime/sys_darwin_386.s
@@ -19,7 +19,13 @@ TEXT runtime·exit(SB),NOSPLIT,$0
 
 // Exit this OS thread (like pthread_exit, which eventually
 // calls __bsdthread_terminate).
-TEXT runtime·exit1(SB),NOSPLIT,$0
+TEXT runtime·exit1(SB),NOSPLIT,$16-0
+	// __bsdthread_terminate takes 4 word-size arguments.
+	// Set them all to 0. (None are an exit status.)
+	MOVL	$0, 0(SP)
+	MOVL	$0, 4(SP)
+	MOVL	$0, 8(SP)
+	MOVL	$0, 12(SP)
 	MOVL	$361, AX
 	INT	$0x80
 	JAE 2(PC)
diff --git a/src/runtime/sys_darwin_amd64.s b/src/runtime/sys_darwin_amd64.s
index e8ae6fac4f..16125b0d4f 100644
--- a/src/runtime/sys_darwin_amd64.s
+++ b/src/runtime/sys_darwin_amd64.s
@@ -26,12 +26,19 @@ TEXT runtime·exit(SB),NOSPLIT,$0
 // Exit this OS thread (like pthread_exit, which eventually
 // calls __bsdthread_terminate).
 TEXT runtime·exit1(SB),NOSPLIT,$0
-	MOVL	code+0(FP), DI		// arg 1 exit status
+	// __bsdthread_terminate takes 4 word-size arguments.
+	// Set them all to 0. (None are an exit status.)
+	MOVL	$0, DI
+	MOVL	$0, SI
+	MOVL	$0, DX
+	MOVL	$0, R10
 	MOVL	$(0x2000000+361), AX	// syscall entry
 	SYSCALL
 	MOVL	$0xf1, 0xf1  // crash
 	RET
 
+
+
 TEXT runtime·open(SB),NOSPLIT,$0
 	MOVQ	name+0(FP), DI		// arg 1 pathname
 	MOVL	mode+8(FP), SI		// arg 2 flags
diff --git a/src/runtime/sys_darwin_arm.s b/src/runtime/sys_darwin_arm.s
index 5def7766b0..d59a3aaa4d 100644
--- a/src/runtime/sys_darwin_arm.s
+++ b/src/runtime/sys_darwin_arm.s
@@ -90,6 +90,12 @@ TEXT runtime·exit(SB),NOSPLIT,$-4
 // Exit this OS thread (like pthread_exit, which eventually
 // calls __bsdthread_terminate).
 TEXT runtime·exit1(SB),NOSPLIT,$0
+	// __bsdthread_terminate takes 4 word-size arguments.
+	// Set them all to 0. (None are an exit status.)
+	MOVW	$0, R0
+	MOVW	$0, R1
+	MOVW	$0, R2
+	MOVW	$0, R3
 	MOVW	$SYS_bsdthread_terminate, R12
 	SWI	$0x80
 	MOVW	$1234, R0
diff --git a/src/runtime/sys_darwin_arm64.s b/src/runtime/sys_darwin_arm64.s
index 34fb1f3086..513f1284ef 100644
--- a/src/runtime/sys_darwin_arm64.s
+++ b/src/runtime/sys_darwin_arm64.s
@@ -90,6 +90,12 @@ TEXT runtime·exit(SB),NOSPLIT,$-8
 // Exit this OS thread (like pthread_exit, which eventually
 // calls __bsdthread_terminate).
 TEXT runtime·exit1(SB),NOSPLIT,$0
+	// __bsdthread_terminate takes 4 word-size arguments.
+	// Set them all to 0. (None are an exit status.)
+	MOVW	$0, R0
+	MOVW	$0, R1
+	MOVW	$0, R2
+	MOVW	$0, R3
 	MOVW	$SYS_bsdthread_terminate, R16
 	SVC	$0x80
 	MOVD	$1234, R0