Closed Bug 1026477 Opened 8 years ago Closed 8 years ago

Assertion failure: parent->isNative(), at vm/Interpreter.cpp:3617


(Core :: JavaScript Engine, defect)

Not set



Tracking Status
firefox33 --- affected


(Reporter: decoder, Assigned: jimb)


(Keywords: assertion, testcase, Whiteboard: [jsbugmon:update])


(3 files)

The following testcase asserts on mozilla-central revision bb35d1b73634 (threadsafe build, run with --fuzzing-safe):

function foo() {
var g = newGlobal();
g.debuggeeGlobal = this;
g.eval("(" + function () {
      dbg = new Debugger(debuggeeGlobal);
      dbg.onExceptionUnwind = function (frame, exc) {
          var s = '!';
          for (var f = frame; f.eval("function f() { debugger; g2.g(); }"); f = f.older)
          debuggeeGlobal.log += s;
  } + ")();");
function f() {
} foo();
Whiteboard: [jsbugmon:update,bisect]
Whiteboard: [jsbugmon:update,bisect] → [jsbugmon:update]
JSBugMon: Bisection requested, result:
autoBisect shows this is probably related to the following changeset:

The first bad revision is:
user:        Shu-yu Guo
date:        Thu Apr 24 01:59:37 2014 -0700
summary:     Bug 716647 - Part 5: Relax the no on-stack scripts restriction for addDebuggee. (r=jimb)

This iteration took 251.733 seconds to run.
Needinfo on shu based on comment 2.
Flags: needinfo?(shu)
I can take this.
Assignee: nobody → jimb
Reduced test case:

var g = newGlobal();
var dbg = new Debugger(g);
dbg.onDebuggerStatement = function (frame) {
  frame.eval('function f() { }');

g.eval('(function () { var f = 42; debugger; })();');
Flags: needinfo?(shu)
Thanks, Jim!
The fuzzers hit this one again. Jim, did this fall off your radar?
Flags: needinfo?(jimb)
The assertion is checking that, when we do frame.eval('function f() { }'), the scope object on which we define f is a native object. It is instead a DebugScopeObject, a proxy that combines Call and Block object properties with stack frame slots to provide a complete view of the frame's environment.

I don't quite know why the assertion is there. But it is definitely necessary to accept DebugScopeObjects as targets of the function definition: I have test cases which demonstrate overwriting both scope object properties and stack frame slots; DebugScopeObjects are the only way to get that behavior.

(Note that the assertion is not concerned with which object gets captured as the function's environment, only with which object gets the new value for 'f'.)
Flags: needinfo?(jimb)
Comment on attachment 8538834 [details] [diff] [review]
Make EvaluateInEnv static to Debugger.cpp; JSD1 no longer uses it

Review of attachment 8538834 [details] [diff] [review]:

(This patch screws up the code's indentation; my local copy has corrected that.)
Attachment #8538834 - Flags: review?(shu)
Attachment #8538838 - Flags: review?(shu)
Attachment #8538834 - Flags: review?(shu) → review+
Attachment #8538838 - Flags: review?(shu) → review+
Jim, is this ready for landing?
Flags: needinfo?(jimb)
Oh, probably! Thanks for the reminder. I'll re-check, and land.
Flags: needinfo?(jimb)
Rebased patch on current M-C. Try push:
Flags: in-testsuite+
OS: Linux → All
Hardware: x86_64 → All
Target Milestone: --- → mozilla38
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