Omit some arguments with paths from Rust hash calculation. Fixes #207, #196 - #345
Merged
Merged
Conversation
…lla#207 Some rustc arguments like --out-dir, -L, and --extern contain absolute paths which make building the same crate (from crates.io) in different projects unable to get cache hits despite being otherwise the same. This patch omits those arguments from the hash calculation which makes sccache much more useful for local development. For additional safety we add the cwd to the hash key, since that winds up in the rlib and otherwise this patch could result in some compiles returning invalid results from cache.
luser
changed the title
tottoto
pushed a commit
to tottoto/sccache
that referenced
this pull request
Feb 6, 2026
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Some rustc arguments like --out-dir, -L, and --extern contain absolute paths
which make building the same crate (from crates.io) in different projects
unable to get cache hits despite being otherwise the same. This patch omits
those arguments from the hash calculation which makes sccache much more useful
for local development.
For additional safety we add the cwd to the hash key, since that winds up in
the rlib and otherwise this patch could result in some compiles returning invalid results from cache.