Fix Issue 19954 - ICE: Casting AliasSeq to array and passing to a function

[JinShil]

Best viewed without whitespace changes.

[thewilsonator]

Stable?

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	19954	normal	ICE: Casting AliasSeq to array and passing to a function

Testing this PR locally

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

dub fetch digger
dub run digger -- build "stable + dmd#10036"

[JinShil]

rebased to stable

[kinke]

Should this really compile? auto a = cast(int[]) 1; doesn't.

[JinShil]

According to this (run "All dmd com"), yes. But I think "" is more analogous to [] than to 1, and auto a = cast(int[])[]; compiles.

[kinke]

Ah, a regression. cast(void[][]) [] does compile too, so all good.

[jacob-carlborg]

Should there be a test that actually casts an AliasSeq to an array, as described in the issue?

[ghost]

Yes please add the test with an alias Seq. If that does not pass then you can add this:

+        if (exp.e1.type.ty == Ttuple)
+        {
+            TupleExp te = exp.e1.isTupleExp();
+            if (te.exps.dim == 1)
+                exp.e1 = (*te.exps)[0];
+        }

around line 6650, just after you're sure that exp.e1.type is a thing.
Theorically tuples with not one element are rejected when implicit conversion is tried.

[JinShil]

Should there be a test that actually casts an AliasSeq to an array, as described in the issue?

Yes, good call. It didn't pass.

If that does pass then you can add this

Thanks, that worked.