diff --git a/js/src/frontend/Parser.cpp b/js/src/frontend/Parser.cpp
index b3a19513f9b9..3ef90bffaf22 100644
--- a/js/src/frontend/Parser.cpp
+++ b/js/src/frontend/Parser.cpp
@@ -7240,7 +7240,7 @@ Parser::primaryExpr(TokenKind tt, JSBool afterDot)
                 pn3 = NullaryNode::create(tc);
                 if (!pn3)
                     return NULL;
-                pn3->pn_dval = tokenStream.currentToken().t_dval;
+                pn3->pn_dval = tokenStream.currentToken().number();
                 if (!js_ValueToAtom(context, DoubleValue(pn3->pn_dval), &atom))
                     return NULL;
                 break;
@@ -7266,7 +7266,7 @@ Parser::primaryExpr(TokenKind tt, JSBool afterDot)
                         pn3 = NullaryNode::create(tc);
                         if (!pn3)
                             return NULL;
-                        pn3->pn_dval = tokenStream.currentToken().t_dval;
+                        pn3->pn_dval = tokenStream.currentToken().number();
                         if (!js_ValueToAtom(context, DoubleValue(pn3->pn_dval), &atom))
                             return NULL;
                     } else {
@@ -7412,7 +7412,7 @@ Parser::primaryExpr(TokenKind tt, JSBool afterDot)
         pn = UnaryNode::create(tc);
         if (!pn)
             return NULL;
-        pn->pn_num = (jsint) tokenStream.currentToken().t_dval;
+        pn->pn_num = tokenStream.currentToken().sharpNumber();
         tt = tokenStream.getToken(TSF_OPERAND);
         pn->pn_kid = primaryExpr(tt, JS_FALSE);
         if (!pn->pn_kid)
@@ -7436,7 +7436,7 @@ Parser::primaryExpr(TokenKind tt, JSBool afterDot)
             return NULL;
         if (!tc->ensureSharpSlots())
             return NULL;
-        pn->pn_num = (jsint) tokenStream.currentToken().t_dval;
+        pn->pn_num = tokenStream.currentToken().sharpNumber();
         break;
 #endif /* JS_HAS_SHARP_VARS */
 
@@ -7667,7 +7667,7 @@ Parser::primaryExpr(TokenKind tt, JSBool afterDot)
         if (!pn)
             return NULL;
         pn->setOp(JSOP_DOUBLE);
-        pn->pn_dval = tokenStream.currentToken().t_dval;
+        pn->pn_dval = tokenStream.currentToken().number();
         break;
 
       case TOK_PRIMARY:
diff --git a/js/src/frontend/TokenStream.cpp b/js/src/frontend/TokenStream.cpp
index bc00f20414f4..652a71ab1320 100644
--- a/js/src/frontend/TokenStream.cpp
+++ b/js/src/frontend/TokenStream.cpp
@@ -1713,7 +1713,7 @@ TokenStream::getTokenInternal()
             if (!js_strtod(cx, numStart, userbuf.addressOfNextRawChar(), &dummy, &dval))
                 goto error;
         }
-        tp->t_dval = dval;
+        tp->setNumber(dval);
         tt = TOK_NUMBER;
         goto out;
     }
@@ -1799,7 +1799,7 @@ TokenStream::getTokenInternal()
         const jschar *dummy;
         if (!GetPrefixInteger(cx, numStart, userbuf.addressOfNextRawChar(), radix, &dummy, &dval))
             goto error;
-        tp->t_dval = dval;
+        tp->setNumber(dval);
         tt = TOK_NUMBER;
         goto out;
     }
@@ -2071,9 +2071,8 @@ TokenStream::getTokenInternal()
                 goto error;
             }
         }
-        tp->t_dval = (jsdouble) n;
-        if (cx->hasStrictOption() &&
-            (c == '=' || c == '#')) {
+        tp->setSharpNumber(uint16(n));
+        if (cx->hasStrictOption() && (c == '=' || c == '#')) {
             char buf[20];
             JS_snprintf(buf, sizeof buf, "#%u%c", n, c);
             if (!ReportCompileErrorNumber(cx, this, NULL, JSREPORT_WARNING | JSREPORT_STRICT,
diff --git a/js/src/frontend/TokenStream.h b/js/src/frontend/TokenStream.h
index 27d52d090a33..47d5758f70d0 100644
--- a/js/src/frontend/TokenStream.h
+++ b/js/src/frontend/TokenStream.h
@@ -265,14 +265,15 @@ struct Token {
                 JSAtom       *atom;     /* potentially-numeric atom */
             } n;
         } s;
-        class {                         /* pair for <?target data?> XML PI */
-            friend struct Token;
+
+      private:
+        friend struct Token;
+        struct {                        /* pair for <?target data?> XML PI */
             JSAtom       *data;         /* auxiliary atom table entry */
             PropertyName *target;       /* main atom table entry */
         } xmlpi;
-        jsdouble        dval;           /* floating point number */
-      private:
-        friend struct Token;
+        uint16          sharpNumber;    /* sharp variable number: #1# or #1= */
+        jsdouble        number;         /* floating point number */
         RegExpFlag      reflags;        /* regexp flags, use tokenbuf to access
                                            regexp chars */
     } u;
@@ -306,6 +307,14 @@ struct Token {
         u.reflags = flags;
     }
 
+    void setSharpNumber(uint16 sharpNum) {
+        u.sharpNumber = sharpNum;
+    }
+
+    void setNumber(jsdouble n) {
+        u.number = n;
+    }
+
     /* Type-safe accessors */
 
     PropertyName *name() const {
@@ -338,10 +347,19 @@ struct Token {
         JS_ASSERT((u.reflags & AllFlags) == u.reflags);
         return u.reflags;
     }
+
+    uint16 sharpNumber() const {
+        JS_ASSERT(type == TOK_DEFSHARP || type == TOK_USESHARP);
+        return u.sharpNumber;
+    }
+
+    jsdouble number() const {
+        JS_ASSERT(type == TOK_NUMBER);
+        return u.number;
+    }
 };
 
 #define t_op            u.s.op
-#define t_dval          u.dval
 
 enum TokenStreamFlags
 {