Bug 763384 - Don't treat regexp syntax errors as OOM errors (r=njn)

js/public/Utility.h

@@ -21,6 +21,7 @@
 #include "jstypes.h"
 
 #ifdef __cplusplus
+# include "mozilla/Scoped.h"
 
 /* The public JS engine namespace. */
 namespace JS {}
@@ -594,6 +595,15 @@ public:
 class UnwantedForeground : public Foreground {
 };
 
+template <typename T>
+struct ScopedDeletePtrTraits
+{
+    typedef T *type;
+    static T *empty() { return NULL; }
+    static void release(T *ptr) { Foreground::delete_(ptr); }
+};
+SCOPED_TEMPLATE(ScopedDeletePtr, ScopedDeletePtrTraits)
+
 } /* namespace js */
 
 /*

js/src/jit-test/tests/basic/testBug763384.js

@@ -0,0 +1,9 @@
+var caught = false;
+try {
+    ''.match('(');
+} catch (e) {
+    caught = true;
+    assertEq(e instanceof Error, true);
+    assertEq(('' + e).indexOf('SyntaxError') === -1, false);
+}
+assertEq(caught, true);

js/src/vm/RegExpObject.cpp

@@ -560,29 +560,26 @@ RegExpCompartment::get(JSContext *cx, JSAtom *keyAtom, JSAtom *source, RegExpFla
         return true;
     }
 
-    RegExpShared *shared = cx->runtime->new_<RegExpShared>(cx->runtime, flags);
+    ScopedDeletePtr<RegExpShared> shared(cx->new_<RegExpShared>(cx->runtime, flags));
     if (!shared)
-        goto error;
+        return false;
 
     if (!shared->compile(cx, source))
-        goto error;
+        return false;
 
     /* Re-lookup in case there was a GC. */
-    if (!map_.relookupOrAdd(p, key, shared))
-        goto error;
+    if (!map_.relookupOrAdd(p, key, shared)) {
+        js_ReportOutOfMemory(cx);
+        return false;
+    }
 
     /*
      * Since 'error' deletes 'shared', only guard 'shared' on success. This is
      * safe since 'shared' cannot be deleted by GC until after the call to
-     * map_.add() directly above.
+     * map_.relookupOrAdd() directly above.
      */
-    g->init(*shared);
+    g->init(*shared.forget());
     return true;
-
-  error:
-    Foreground::delete_(shared);
-    js_ReportOutOfMemory(cx);
-    return false;
 }
 
 bool