fix issue 20937 - std.range.array of a lengthless range with indirection is not @safe

[dukc]

Also replaced emplaceRef with emplace to remove dependency on DRuntime internals.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	20937	normal	std.range.array of a lengthless range with indirection is not @safe

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 "stable + phobos#8202"

[thewilsonator]

It seems this fails CI

[RazvanN7]

This seems to have uncovered an ICE in the compiler.

[RazvanN7]

Does this work as intended if emplaceRef is used?

[dukc]

Let's test...

[dukc]

Nope, does not. Changing back.

EDIT: oops, was watching old autotest results. Let's try once more

[dukc]

Now I'm definitely seeing an ICE with emplaceRef version. Hopefully this is the last switchback I'll do

[dukc]

Ouch, we have a heisenbug indeed. Even though I'm using the latest Linux dmd, compiling the same file with same flags as the autotester, the ICE does not reproduce locally.

EDIT: again bad reading of autotester reports on my part. I looked at last command before the error instead of the "command failed" line after the stack trace. Now I can reproduce.

[dukc]

DMD issue pinned - reported here: https://issues.dlang.org/show_bug.cgi?id=22228

[BorisCarvajal]

Sorry, I should've target master in dlang/dmd#13007 . But you know, someone could say regressions go to stable, no exceptions.

I suppose an early merge should be possible. (HELP!)

[RazvanN7]

@dukc Please rebase against stable so that we can get this in.

[dukc]

Sorry, I should've target master in dlang/dmd#13007 . But you know, someone could say regressions go to stable, no exceptions.

I suppose an early merge should be possible. (HELP!)

Since the PR that caused the bug in first place was merged into stable, it was correct thing to do to target stable yourself. It's up to me to rebase in situations like these. Alternatively I could just have waited for the stable merge in DMD.

[dukc]

CircleCI fails because... DMD fails to build?

[RazvanN7]

Are you sure you are using the latest stable branch?

[dukc]

I update my local stable, then rebased my local PR branch against that and then force-pushed. And also I changed this PR:s target branch.

My fork repo still compares the PR branch against master though - how do I rebase that?