1 files changed, 3 insertions, 2 deletions

diff --git a/src/lj_ir.h b/src/lj_ir.h
index a801d5d0..6116f7e5 100644
--- a/src/lj_ir.h
+++ b/src/lj_ir.h
@@ -413,11 +413,12 @@ static LJ_AINLINE IRType itype2irt(const TValue *tv)
 
 static LJ_AINLINE uint32_t irt_toitype_(IRType t)
 {
-  lua_assert(!LJ_64 || LJ_GC64 || t != IRT_LIGHTUD);
+  lj_assertX(!LJ_64 || LJ_GC64 || t != IRT_LIGHTUD,
+             "no plain type tag for lightuserdata");
   if (LJ_DUALNUM && t > IRT_NUM) {
     return LJ_TISNUM;
   } else {
-    lua_assert(t <= IRT_NUM);
+    lj_assertX(t <= IRT_NUM, "no plain type tag for IR type %d", t);
     return ~(uint32_t)t;
   }
 }