Use response files when spawning rustc commands when needed - #2789
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Use response files when spawning rustc commands when needed#2789ranger-ross wants to merge 1 commit into
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ranger-ross
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Aug 1, 2026
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| // On Windows there is a hard limit of ~32KB, so we cut off at 30KB to | ||
| // give some buffer just incase. | ||
| #[cfg(windows)] | ||
| let threshold: usize = 30 * 1024; | ||
| // On unix the limit is defined by ARG_MAX. If its not explicitly set we set it to 1MB | ||
| // which is fairly large but lower than the ~2MB that it defaults to on most systems. | ||
| #[cfg(unix)] | ||
| let threshold: usize = std::env::var("ARG_MAX") | ||
| .ok() | ||
| .and_then(|v| v.parse().ok()) | ||
| .unwrap_or(1024 * 1024); |
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Took these thresholds from rustc, see
Codecov Report❌ Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## main #2789 +/- ##
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- Coverage 74.32% 74.31% -0.02%
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Files 72 72
Lines 40772 40821 +49
==========================================
+ Hits 30305 30336 +31
- Misses 10467 10485 +18 ☔ View full report in Codecov by Harness. 🚀 New features to boost your workflow:
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CI failures should be unrelated to this change. |
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This is a follow up on #2782.
Unfortunately, I overlooked the fact that sccache modifies the args and does not pass the exact args to rustc that it receives.
This leads to the expanded args getting passed to rustc which blows up on windows when the command is large enough.
The solution is to have sccache create its own arg file (when needed) to pass the args to rustc.
fixes #2787
(I tested the repo in question and it fails without these changes and builds successfully with them)