1 files changed, 6 insertions, 0 deletions
diff --git a/test/bun.js/ffi.test.fixture.callback.c b/test/bun.js/ffi.test.fixture.callback.c
index bd912dde2..f6e74f8ba 100644
--- a/test/bun.js/ffi.test.fixture.callback.c
+++ b/test/bun.js/ffi.test.fixture.callback.c
@@ -149,11 +149,17 @@ static bool JSVALUE_IS_NUMBER(EncodedJSValue val) {
 
 static void* JSVALUE_TO_PTR(EncodedJSValue val) {
   // must be a double
+  if (val.asInt64 == TagValueNull)
+    return 0;
   return (void*)(val.asInt64 - DoubleEncodeOffset);
 }
 
 static EncodedJSValue PTR_TO_JSVALUE(void* ptr) {
   EncodedJSValue val;
+  if (ptr == 0) {
+    val.asInt64 = TagValueNull;
+    return val;
+  }
   val.asInt64 = (int64_t)ptr + DoubleEncodeOffset;
   return val;
 }