diff --git a/js/src/jsemit.cpp b/js/src/jsemit.cpp
index df4125777e8b..4d457604bae1 100644
--- a/js/src/jsemit.cpp
+++ b/js/src/jsemit.cpp
@@ -5797,12 +5797,7 @@ js_EmitTree(JSContext *cx, JSCodeGenerator *cg, JSParseNode *pn)
 
 #if JS_HAS_GENERATORS
       case TOK_YIELD:
-        if (!cg->inFunction()) {
-            ReportCompileErrorNumber(cx, CG_TS(cg), pn, JSREPORT_ERROR,
-                                     JSMSG_BAD_RETURN_OR_YIELD,
-                                     js_yield_str);
-            return JS_FALSE;
-        }
+        JS_ASSERT(cg->inFunction());
         if (pn->pn_kid) {
             if (!js_EmitTree(cx, cg, pn->pn_kid))
                 return JS_FALSE;
diff --git a/js/src/jsparse.cpp b/js/src/jsparse.cpp
index c7359707c985..34023d77a7d5 100644
--- a/js/src/jsparse.cpp
+++ b/js/src/jsparse.cpp
@@ -4786,8 +4786,13 @@ Parser::returnOrYield(bool useAssignExpr)
         return NULL;
 
 #if JS_HAS_GENERATORS
-    if (tt == TOK_YIELD)
+    if (tt == TOK_YIELD) {
+        if (!tc->inFunction()) {
+            reportErrorNumber(NULL, JSREPORT_ERROR, JSMSG_BAD_RETURN_OR_YIELD, js_yield_str);
+            return NULL;
+        }
         tc->flags |= TCF_FUN_IS_GENERATOR;
+    }
 #endif
 
     /* This is ugly, but we don't want to require a semicolon. */
diff --git a/js/src/tests/js1_8_5/extensions/reflect-parse.js b/js/src/tests/js1_8_5/extensions/reflect-parse.js
index 97bbc76e9465..74d26f773950 100644
--- a/js/src/tests/js1_8_5/extensions/reflect-parse.js
+++ b/js/src/tests/js1_8_5/extensions/reflect-parse.js
@@ -390,6 +390,17 @@ assertStmt("try { } catch (e if foo) { } catch (e if bar) { } catch (e) { } fina
                      catchClause(ident("e"), null, blockStmt([])) ],
                    blockStmt([])));
 
+// Bug 632028: yield outside of a function should throw
+(function() {
+    var threw = false;
+    try {
+        Reflect.parse("yield 0");
+    } catch (expected) {
+        threw = true;
+    }
+    assertEq(threw, true);
+})();
+
 // redeclarations (TOK_NAME nodes with lexdef)
 
 assertStmt("function f() { function g() { } function g() { } }",