error_index_generator in 1.24.0 fails to build using 1.24.0, entity not found

[kyrias]

I can build rust 1.24.0 using our 1.23.0 package, but when I try to build 1.24.0 again using the 1.24.0 package I already built I get the following error during python2 ./x.py install:

Documenting error index (x86_64-unknown-linux-gnu)
Building stage2 tool error_index_generator (x86_64-unknown-linux-gnu)
   Compiling error_index_generator v0.0.0 (file:///build/rust/src/rustc-1.24.0-src/src/tools/error_index_generator)
    Finished release [optimized] target(s) in 4.3 secs
thread 'main' panicked at 'entity not found', tools/error_index_generator/main.rs:209:9
note: Run with `RUST_BACKTRACE=1` for a backtrace.


command did not execute successfully: "/build/rust/src/rustc-1.24.0-src/build/x86_64-unknown-linux-gnu/stage2-tools-bin/error_index_generator" "html" "/build/rust/src/rustc-1.24.0-src/build/x86_64-unknown-linux-gnu/doc/error-index.html"
expected success, got: exit code: 101


failed to run: /build/rust/src/rustc-1.24.0-src/build/bootstrap/debug/bootstrap install
Build completed unsuccessfully in 0:01:47

[Mark-Simulacrum]

Looks like maybe we didn't generate the relevant metadata. Could you provide the full log by chance?

[kyrias]

@Mark-Simulacrum https://ptpb.pw/bkT0

[cuviper]

This was seen on Fedora too, in the build.log here:
https://koji.fedoraproject.org/koji/taskinfo?taskID=25212630

[cuviper]

To get away from distro idiosyncrasies, I tried default builds of stable, beta, and nightly, just pointing each to their matching --local-rust-root ~/.rustup/toolchains/{stable,beta,nightly}... for a local rebuild. Stable (1.24) still failed, but beta and nightly were fine.

[cuviper]

The actual error via strace is:

open("tmp/extended-errors/x86_64-unknown-linux-gnu", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1 ENOENT (No such file or directory)

I strongly suspect we need 8c9bf66 from #47141.

[cuviper]

I backported that commit to stable, without the unrelated stage0-diagnostic stuff, and it seems to work:
cuviper@b445a52

[Mark-Simulacrum]

Thanks for experimenting! Since it's looking like we might be releasing 1.24.1 anyway (due to a variety of regressions that where detected post-release) I'll try to make sure that patch makes it into that.

[nikomatsakis]

triage: P-high

Gotta get this fixed.