@@ -35,14 +35,15 @@
 	; arg 2 = syscall num
 	; arg 3 = valency
 	; arg 4 = args ptr
 
-	; we use two registers that are supposed
+	; we use three registers that are supposed
 	; to be callee-saved, so we need to
 	; push them to the stack and then pop
 	; them back off just before the fn rets.
 	push rbx
 	push r12
+	push r15
 
 	; store the locals in registers that
 	; are guaranteed not to be clobbered,
 	; saving us some cycles pushing to
@@ -102,7 +103,8 @@
 	        mov qword [rbx], -1
 			mov       [r12], sys.reg.ret
 			jmp .return
 
-	.return: pop r12
+	.return: pop r15 
+		 pop r12
 	         pop rbx
 			 ret