Relation with Tail Call Elimination

[claudepache]

When frames are elided because of Tail Call Elimination, should they also be omitted from the stack trace? Experience with JSC shows that it is indeed the case for them; here is a testcase:

(function foo() { 
    "use strict"; 
    function bar() { return new Error }
    return bar()
})().stack

[mk-pmb]

What were the pros/cons that lead to "that it is indeed the case for them"? The example is a special case in that

• bar is defined in the same scope where it's called.
• bar is called from only one place.
• bar has no arguments that a JS engine might want to track. (afaik they aren't tracked usually, are they?)

[ljharb]

The feature you’re referring to is Proper Tail Calls; since this proposal only specifies the format of the stack, and not its contents, it does not interact with PTC.

However, this proposal does build a foundation on which a followup proposal could specify the contents.