Get rid of double indirection in string interner

[petrochenkov]

No description provided.

[rust-highfive]

r? @alexcrichton

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[alexcrichton]

@bors: r+

cc @rust-lang/libs, just a heads up about this unstable API. Seems fine for compiler perf but I think it's something we'll want to handle regardless one day anyway.

[bors]

📌 Commit 6d06280 has been approved by alexcrichton

[bors]

⌛ Testing commit 6d06280 with merge c77dcf4...

[bors]

💔 Test failed - auto-linux-cross-opt

[petrochenkov]

@bors r=alexcrichton

[bors]

💡 This pull request was already approved, no need to approve it again.

• This pull request previously failed. You should add more commits to fix the bug, or use retry to trigger a build again.

[bors]

📌 Commit 6d06280 has been approved by alexcrichton

[petrochenkov]

@bors retry

[bors]

⌛ Testing commit 6d06280 with merge bb9e151...

[bors]

💔 Test failed - auto-linux-cross-opt

[bluss]

Will the sized deallocation even be correct? This code is a bit Jackie than the standard for libs.

[bluss]

Hackier.

[petrochenkov]

@bluss

Will the sized deallocation even be correct?

Yes, deallocation size (size_of_val) and allocation size (aligned_len * sizeof(usize)) are supposed to be equal, that's why I set the "metadata" part of the fat pointer and align up the allocation size.
It'd be nice to have some safer (non-coercion) way to create DST structs, but there's none at the moment (to my knowledge).

[petrochenkov]

@bluss
I've added an assert for allocation/deallocation sizes.

[bluss]

Oh cool, I see. I didn't realize even the trailing end would be rounded up to alignment.

[petrochenkov]

Aha, buildbot is alive again.
@bors r=alexcrichton

[bors]

📌 Commit 348c3fb has been approved by alexcrichton

[bors]

⌛ Testing commit 348c3fb with merge 5bfe107...

[bors]

☀️ Test successful - auto-linux-32-nopt-t, auto-linux-32-opt, auto-linux-64-cargotest, auto-linux-64-cross-freebsd, auto-linux-64-debug-opt, auto-linux-64-nopt-t, auto-linux-64-opt, auto-linux-64-opt-rustbuild, auto-linux-64-x-android-t, auto-linux-cross-opt, auto-linux-musl-64-opt, auto-mac-32-opt, auto-mac-64-opt, auto-mac-64-opt-rustbuild, auto-mac-cross-ios-opt, auto-win-gnu-32-opt, auto-win-gnu-32-opt-rustbuild, auto-win-gnu-64-opt, auto-win-msvc-32-opt, auto-win-msvc-64-cargotest, auto-win-msvc-64-opt, auto-win-msvc-64-opt-rustbuild
Approved by: alexcrichton
Pushing 5bfe107 to master...