diff --git a/src/lj_asm_arm.h b/src/lj_asm_arm.h
index ef907fbe..5a628b3b 100644
--- a/src/lj_asm_arm.h
+++ b/src/lj_asm_arm.h
@@ -355,7 +355,7 @@ static void asm_gencall(ASMState *as, const CCallInfo *ci, IRRef *args)
     IRRef ref = args[n];
     IRIns *ir = IR(ref);
 #if !LJ_SOFTFP
-    if (irt_isfp(ir->t)) {
+    if (ref && irt_isfp(ir->t)) {
       RegSet of = as->freeset;
       Reg src;
       if (!LJ_ABI_SOFTFP && !(ci->flags & CCI_VARARG)) {