fix Issue 22774 - TraceInfo is gathered only once when throwing a Thr…

[mkykadir]

…owable

Update info during every throw

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	22774	minor	TraceInfo is gathered only once when throwing a Throwable

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + druntime#3742"

[thewilsonator]

I think the fix for this should be in user code to set t.info = null if you want a new trace using the same throwable object.

[Geod24]

I think the fix for this should be in user code [...]

Why would one want this behavior ?

[thewilsonator]

Unless the red in the CI is unrelated, then this break a whole lot of stuff.

[mkykadir]

Unless the red in the CI is unrelated, then this break a whole lot of stuff.

Investigating this but generally time-out during fail-compilation tests (randomly); for example stuck at
... fail_compilation/test16116.d -verrors=0 -m64 -fPIC ()

[mkykadir]

OK, one of the causes that I could find is this, this changeset conflicts with it. Exceptional cases when GC cannot be trusted (i.e. memory exceptions) are single instanced; and TraceInfo should not be constructed; this changeset causes that.

[kinke]

I think the fix for this should be in user code [...]

Why would one want this behavior ?

In C#, there's a difference between throw; (a rethrow with the same context) and throw e; (new context): https://stackoverflow.com/questions/730250/is-there-a-difference-between-throw-and-throw-ex

In D:

try { foo(); }
catch (Exception e) { logException(e); throw e; } // keep the existing TraceInfo!