remove optabgen.d

[WalterBright]

Completes removal of optabgen.d

[dlang-bot]

Thanks for your pull request, @WalterBright!

Bugzilla references

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If your PR contains non-trivial changes, please reference a Bugzilla issue or create a manual changelog.

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 "master + dmd#10221"

[rainers]

Please keep CRLF for the vcxproj files.

[rainers]

LGTM, but the failure on semaphoreci seems to persist: looks like the check for reproducible builds fails consistently

[Geod24]

The SemaphoreCI failure wasn't resolved AFAICS ? And it was indeed consistent, I restarted it myself a few times...

[MartinNowak]

Thanks, this inadvertently finally fixed the nightly builds which were broken on Windows with a 2.087.0 host compiler (e.g. https://buildkite.com/dlang/build-release/builds/329#b9498950-3d55-4cd8-be91-5dc305a7d527/6-8989).

@wilzbach @rainers
I guess we're not testing building dmd with the latest release version on Windows. The last release cycle also had a major nightly outage due to a Windows build error (see #10045). Can we do something akin to the SemaphoreCI tests on Windows to prevent this in the future?

The Azure job seems to run with a fixed HOST_DMD_VERSION=2.084.1 which isn't strictly necessary with our policy to only guarantee compatibility with the lastest releast dmd compiler as host. Maybe Azure could just be changed to use http://downloads.dlang.org/releases/LATEST instead of the hard-coded version?

Ability to test self-hosting and reproducible builds on Windows would also be nice, but less important.

[rainers]

Maybe Azure could just be changed to use http://downloads.dlang.org/releases/LATEST instead of the hard-coded version?

#10253