Bug 674522 - Fix jsval_layout on 64-bit big-endian platforms (r=waldo)

js/src/jsval.h

@@ -313,7 +313,6 @@ typedef union jsval_layout
             int32          i32;
             uint32         u32;
             JSWhyMagic     why;
-            jsuword        word;
         } payload;
     } s;
     double asDouble;
@@ -350,11 +349,11 @@ typedef union jsval_layout
         uint64             payload47 : 47;
     } debugView;
     struct {
+        uint32             padding;
         union {
             int32          i32;
             uint32         u32;
             JSWhyMagic     why;
-            jsuword        word;
         } payload;
     } s;
     double asDouble;
@@ -363,6 +362,8 @@ typedef union jsval_layout
 # endif /* JS_BITS_PER_WORD */
 #endif  /* defined(IS_LITTLE_ENDIAN) */
 
+JS_STATIC_ASSERT(sizeof(jsval_layout) == 8);
+
 #if JS_BITS_PER_WORD == 32
 
 /*

js/src/jsvalue.h

@@ -743,7 +743,11 @@ class Value
     }
 
     const jsuword *payloadWord() const {
-        return &data.s.payload.word;
+#if JS_BITS_PER_WORD == 32
+        return reinterpret_cast<const jsuword *>(&data.s.payload.word);
+#elif JS_BITS_PER_WORD == 64
+        return reinterpret_cast<const jsuword *>(&data.asBits);
+#endif
     }
 
   private: