rust: don't build out of tree

[ognevny]

this is not supported upstream, but a workaround was used. set build-dir in config.toml, make dest dirs names contain $MSYSTEM to match previous behavior

asking @filnet as a workaround's author is it ok to do so

[filnet]

asking @filnet as a workaround's author is it ok to do so

I am not sure that I understand your question.
But note that I have currently lost interest in Rust (might come back some day though).

[ognevny]

I meant will be fine to drop workaround for building outside of rustc src and build inside of it?

[filnet]

I meant will be fine to drop workaround for building outside of rustc src and build inside of it?

I think that workaround was already in place when I got involved in Rust maintenance.

[ognevny]

oh, I didn't look carefully at blame...

[ognevny]

ok, seems it's fine to do so...

[jeremyd2019]

I was going to mention, we were running right up against the MAX_PATH limits for this package, and moving the build directory deeper would probably make it too deep. Sure enough:

BUG: compat/win32/fscache.c:128: Trying to allocate fsentry for long path 'B/src/rustc-1.83.0-src/build-CLANGARM64/aarch64-pc-windows-gnullvm/stage0-sysroot/lib/rustlib/rustc-src/rust/build-CLANGARM64/aarch64-pc-windows-gnullvm/stage0-sysroot/lib/rustlib/rustc-src/rust/build-CLANGARM64/aarch64-pc-windows-gnullvm/stage0-sysroot/lib/rustlib/rustc-src/rust/build-CLANGARM64/aarch64-pc-windows-gnullvm/stage0-sysroot/lib/rustlib/rustc-src/rust/build-CLANGARM64/aarch64-pc-windows-gnullvm/stage0-sysroot/lib/rustlib/rustc-src/rust/build-CLANGARM64/aarch64-pc-windows-gnullvm/stage0-sysroot/lib/rustlib/rustc-src/rust/build-CLANGARM64/aarch64-pc-windows-gnullvm/stage0-sysroot/lib/rustlib/rustc-src/rust/build-CLANGARM64/aarch64-pc-windows-gnullvm/stage0-sysroot/lib/rustlib/rustc-src/rust/build-CLANGARM64/aarch64-pc-windows-gnullvm/stage0-sysroot/lib/rustlib/rustc-src/rust/build-CLANGARM64/aarch64-pc-windows-gnullvm/stage0-sysroot/lib/rustlib/rustc-src/rust/build-CLANGARM64/aarch64-pc-windows-gnullvm/stage0-sysroot/lib/rus

this seems even weirder than that though, some sort of circular link that git is unhappy with. (I'm running rmdir /s B to try to help get this unstuck)

[ognevny]

oh, but what to do with out-of-tree builds? there should be a better way maybe :(

[jeremyd2019]

I opened git-for-windows/git#5320 for the git BUG output, git clean seems to be following directory junctions rather than simply removing them