v0.17.0

sccache 0.17.0

Summary

sccache 0.17.0 is a significant release: it introduces a new client-side architecture.

Until now, every compilation was handed off to the long-lived sccache server, which did the cache
lookup and ran the compiler. In client-side mode, the client process does that work itself - the
server is only consulted for the shared state it owns (compiler info, dist client, stats). This
removes a round-trip and the server-side bottleneck, and gives noticeably better results on
developer workstations.

Client-side mode is opt-in for now: enable it with the SCCACHE_CLIENT_SIDE environment variable
(or the client_side_mode config key). See docs/Architecture.md
for the details.

Other highlights:

• Response files: gcc/clang builds using quoted @response files are now cached and
  distributed correctly (#2755, #2772), and Rust @argfile arguments are supported (#2782).
• Distributed compilation: compile tasks and their subprocesses are now aborted when a client
  disconnects, instead of running to completion on the build server (#2761, #2774). The
  ToolchainPackager cfg gate was fixed so the dist code builds on ppc64le and s390x (#2749).
• S3 SSE-KMS: server-side encryption with KMS keys is now supported (#2770).
• Diagnostics: gcc color diagnostics now behave the same way as rustc's (#2758).
• Preprocessor correctness: -ivfsoverlay is treated as a preprocessor-only argument (#2767).

Welcome to 4 new contributors!

Client-side mode

• Initial client-side implementation by @glandium in #2735
• doc: document client-side and direct modes in Architecture.md by @sylvestre in #2752

Features

• gcc/clang: cache and distribute builds using quoted @response files by @avikivity in #2755
• Add support for arg files in Rust by @ranger-ross in #2782
• feat: support S3 SSE-KMS by @jpadilla in #2770
• Make gcc diagnostics color output work the same as for rustc by @jwidauer in #2758
• Abort compile tasks and associated subprocesses when a client disconnects by @trxcllnt in #2761

Fixes

• Fix ToolchainPackager cfg gate to build on ppc64le/s390x by @cryptomilk in #2749
• treat -ivfsoverlay as a preprocessor-only argument by @glandium in #2767
• gcc: refine response-file tokenizer visibility and whitespace handling by @sylvestre in #2772
• Fix description of Unix socket-based Redis connection by @Toorero in #2769

Cleanup

• Simplify the code from pr #2761 by @sylvestre in #2774
• tests: pin libc in the dist test crate by @sylvestre in #2784
• Release 0.17.0 by @sylvestre in #2783

New Contributors

• @jwidauer made their first contribution in #2758
• @jpadilla made their first contribution in #2770
• @ranger-ross made their first contribution in #2782
• @Toorero made their first contribution in #2769

Full Changelog: v0.16.0...v0.17.0