1469350 - Debugger.Frame.onPop should not allow reentering a generator that is already on the stack

Status: RESOLVED FIXED

(Core :: JavaScript Engine, enhancement)

Description

[Jason Orendorff [:jorendorff]]

The language spec prevents generators from being re-entered while on stack; Debugger should honor that.

At present this is not such a bad bug, but when we start persisting Debugger.Frames across yield, this would put the same Debugger.Frame on the stack in two places, probably causing a cycle in the `frame.older` chain if not worse.

Comment 1

[Jason Orendorff [:jorendorff]]

Attachment: Debugger.Frame.onPop should not allow reentering a generator that is already on the stack

Comment 2

[Jason Orendorff [:jorendorff]]

Comment on attachment 8985991 [details] [diff] [review]
Debugger.Frame.onPop should not allow reentering a generator that is already on the stack

Retracting r? while I track down a bug

Comment 3

[Jason Orendorff [:jorendorff]]

Comment on attachment 8985991 [details] [diff] [review]
Debugger.Frame.onPop should not allow reentering a generator that is already on the stack

Oh, the failing test was one I wrote for some other changeset, never checked in. So never mind that...

Comment 4

[Jason Orendorff [:jorendorff]]

Attachment: Debugger.Frame.onPop should not allow reentering a generator that is already on the stack

Comment 5

[Jason Orendorff [:jorendorff]]

Attachment: Debugger.Frame.onPop should not allow reentering a generator that is already on the stack

We prevent it by poking the generator's status field while onPop hooks are
running. Async functions get the same treatment, for consistency, although it
is apparently impossible to reenter them anyway.

Comment 6

[Jason Orendorff [:jorendorff]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/9bdec96cf9385318ba79f0d2825616ea7bbaf456

Comment 7

[Eliza Balazs [:ebalazs_]]

https://hg.mozilla.org/mozilla-central/rev/9bdec96cf938