Bug 1022773 - Return value rooting for SPS, r=ehsan

mozilla-spidermonkey · Jun 25, 2014 · 66b03ed · 66b03ed
1 parent 3033608
commit 66b03ed
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Showing 2 changed files with 16 additions and 8 deletions.
diff --git a/tools/profiler/ProfileEntry.cpp b/tools/profiler/ProfileEntry.cpp
@@ -480,10 +480,14 @@ JSObject* ThreadProfile::ToJSObject(JSContext *aCx)
 {
   JS::RootedValue val(aCx);
   std::stringstream ss;
-  JSStreamWriter b(ss);
-  StreamJSObject(b);
-  NS_ConvertUTF8toUTF16 js_string(nsDependentCString(ss.str().c_str()));
-  JS_ParseJSON(aCx, static_cast<const jschar*>(js_string.get()), js_string.Length(), &val);
+  {
+    // Define a scope to prevent a moving GC during ~JSStreamWriter from
+    // trashing the return value.
+    JSStreamWriter b(ss);
+    StreamJSObject(b);
+    NS_ConvertUTF8toUTF16 js_string(nsDependentCString(ss.str().c_str()));
+    JS_ParseJSON(aCx, static_cast<const jschar*>(js_string.get()), js_string.Length(), &val);
+  }
   return &val.toObject();
 }
 

diff --git a/tools/profiler/TableTicker.cpp b/tools/profiler/TableTicker.cpp
@@ -170,10 +170,14 @@ JSObject* TableTicker::ToJSObject(JSContext *aCx)
 {
   JS::RootedValue val(aCx);
   std::stringstream ss;
-  JSStreamWriter b(ss);
-  StreamJSObject(b);
-  NS_ConvertUTF8toUTF16 js_string(nsDependentCString(ss.str().c_str()));
-  JS_ParseJSON(aCx, static_cast<const jschar*>(js_string.get()), js_string.Length(), &val);
+  {
+    // Define a scope to prevent a moving GC during ~JSStreamWriter from
+    // trashing the return value.
+    JSStreamWriter b(ss);
+    StreamJSObject(b);
+    NS_ConvertUTF8toUTF16 js_string(nsDependentCString(ss.str().c_str()));
+    JS_ParseJSON(aCx, static_cast<const jschar*>(js_string.get()), js_string.Length(), &val);
+  }
   return &val.toObject();
 }