diff --git a/asm.js b/asm.js
index 4128148..7db3575 100644
--- a/asm.js
+++ b/asm.js
@@ -1156,13 +1156,15 @@ export class Assembler {
 
     uleb128(x) {
         const bytes = [];
-        do {
+        while (true) {
             const b = x & 0x7f;
             x >>= 7;
-            if (x != 0)
-                b |= 0x80;
-            bytes.push(b);
-        } while (x != 0);
+            if (x == 0) {
+                bytes.push(b);
+                return bytes;
+            }
+            bytes.push(b | 0x80);
+        }
         return bytes;
     }