Changeset 209028 in webkit

Timestamp:

Nov 28, 2016 3:14:43 PM (7 years ago)

Author:

mark.lam@apple.com

Message:

Fix exception scope verification failures in JSScope.cpp.
​https://bugs.webkit.org/show_bug.cgi?id=165047

Reviewed by Saam Barati.

• runtime/JSScope.cpp:

(JSC::JSScope::resolve):

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• runtime/JSScope.cpp (modified) (3 diffs)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2016-11-28  Mark Lam  <mark.lam@apple.com>
+
+        Fix exception scope verification failures in JSScope.cpp.
+        https://bugs.webkit.org/show_bug.cgi?id=165047
+
+        Reviewed by Saam Barati.
+
+        * runtime/JSScope.cpp:
+        (JSC::JSScope::resolve):
+
 2016-11-28  Mark Lam  <mark.lam@apple.com>
 

trunk/Source/JavaScriptCore/runtime/JSScope.cpp

@@ -27 +27 @@
 #include "JSScope.h"
 
+#include "Exception.h"
 #include "JSGlobalObject.h"
 #include "JSLexicalEnvironment.h"
@@ -230 +231 @@
             JSScope* globalScopeExtension = scope->globalObject(vm)->globalScopeExtension();
             if (UNLIKELY(globalScopeExtension)) {
-                if (object->hasProperty(exec, ident))
+                bool hasProperty = object->hasProperty(exec, ident);
+                RETURN_IF_EXCEPTION(throwScope, nullptr);
+                if (hasProperty)
                     return object;
                 JSObject* extensionScopeObject = JSScope::objectAtScope(globalScopeExtension);
-                if (extensionScopeObject->hasProperty(exec, ident))
+                hasProperty = extensionScopeObject->hasProperty(exec, ident);
+                RETURN_IF_EXCEPTION(throwScope, nullptr);
+                if (hasProperty)
                     return extensionScopeObject;
             }
@@ -239 +244 @@
         }
 
-        if (object->hasProperty(exec, ident)) {
-            if (!isUnscopable(exec, scope, object, ident))
+        bool hasProperty = object->hasProperty(exec, ident);
+        RETURN_IF_EXCEPTION(throwScope, nullptr);
+        if (hasProperty) {
+            bool unscopable = isUnscopable(exec, scope, object, ident);
+            ASSERT(!throwScope.exception() || !unscopable);
+            if (!unscopable)
                 return object;
-            ASSERT_WITH_MESSAGE_UNUSED(throwScope, !throwScope.exception(), "When an exception occurs, the result of isUnscopable becomes false");
         }
     }