fix issue24534 : goto can skip declarations in labeled statements without error

[benjones]

Seems like a hacky fix to me since it doesn't seem like a label statement should be creating a new scope at all. I didn't look at what analysis the ctorflow call is doing, but I assume that's the reason it was like this?

Thoughts?

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	24534	normal	Having a label on a declaration makes it possible to skip it with goto

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 + dmd#16510"

[benjones]

Tests failing because of the issue in the backend which revealed the bug:

-----------------------------------------------------------
src/dmd/backend/cod1.d(1178): Error: `goto` skips declaration of variable `dmd.backend.cod1.getlvalue.idxregs`
src/dmd/backend/cod1.d(1185):        declared here

I'll try to fix that in another PR (declaration is in the middle of an 800 line function, so will require a bit of untangling)

[rikkimax]

Doesn't look like a bug to me for PR or for the backend code.

dmd/compiler/src/dmd/backend/cod1.d

Line 1343 in 8f08a4b

Lptr:

The PR is doing exactly what I would expect it to do, error on code that was written with a C style (with multiple labels).

[Herringway]

Doesn't look like a bug to me for PR or for the backend code.

dmd/compiler/src/dmd/backend/cod1.d

Line 1343 in 8f08a4b

Lptr:

The PR is doing exactly what I would expect it to do, error on code that was written with a C style (with multiple labels).

That's the bug... The compiler should not be relying on illegal D code.

[benjones]

Blocked by a phobos issue: dlang/phobos#9003