Allow specifying a custom output directory #1657
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This commit adds support to allow specifying a custom output directory to Cargo. First, the `build.target-dir` configuration key is checked, and failing that the `CARGO_TARGET_DIR` environment variable is checked, and failing that the root package's directory joined with the directory name "target" is used. There are a few caveats to switching target directories, however: * If the target directory is in the current source tree, and the folder name is not called "target", then Cargo may walk the output directory when determining whether a tree is fresh. * If the target directory is not called "target", then Cargo may look inside it currently for `Cargo.toml` files to learn about local packages. * Concurrent usage of Cargo will still result in badness (rust-lang#354), and this is now exascerbated because many Cargo projects can share the same output directory. * The top-level crate is not cached for future compilations, so if a crate is built into directory `foo` and then that crate is later used as a dependency, it will be recompiled. The naming limitations can be overcome in time, but for now it greatly simplifies the crawling routines and shouldn't have much of a negative impact other than some Cargo runtimes (which can in turn be negated by following the "target" name convention). Closes rust-lang#482
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r? @huonw (rust_highfive has picked a reviewer for you, use r? to override) |
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r? @wycats cc @larsbergstrom, @metajack, I believe you guys have wanted this in Servo for some time now |
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Am I correct that this is a solution for target directory sharing? |
alexcrichton
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@metajack yeah, I would expect Servo to check in a top-level Alternatively Servo's build system would set the |
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@alexcrichton thank you very much! |
Hm, doesn't checking in |
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Right, but |
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For servo it's probably OK, I'm more thinking about this as a general footgun. |
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(I don't really have anything concrete to offer to fix/mitigate it, and have no idea if it'll be a problem in practice.) |
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r? @brson |
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@bors r+ |
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📌 Commit 014765f has been approved by |
This commit adds support to allow specifying a custom output directory to Cargo. First, the `build.target-dir` configuration key is checked, and failing that the `CARGO_TARGET_DIR` environment variable is checked, and failing that the root package's directory joined with the directory name "target" is used. There are a few caveats to switching target directories, however: * If the target directory is in the current source tree, and the folder name is not called "target", then Cargo may walk the output directory when determining whether a tree is fresh. * If the target directory is not called "target", then Cargo may look inside it currently for `Cargo.toml` files to learn about local packages. * Concurrent usage of Cargo will still result in badness (#354), and this is now exascerbated because many Cargo projects can share the same output directory. * The top-level crate is not cached for future compilations, so if a crate is built into directory `foo` and then that crate is later used as a dependency, it will be recompiled. The naming limitations can be overcome in time, but for now it greatly simplifies the crawling routines and shouldn't have much of a negative impact other than some Cargo runtimes (which can in turn be negated by following the "target" name convention). Closes #482
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☀️ Test successful - cargo-linux-32, cargo-linux-64, cargo-mac-32, cargo-mac-64, cargo-win-gnu-32, cargo-win-gnu-64 |
This commit adds support to allow specifying a custom output directory to Cargo.
First, the
build.target-dirconfiguration key is checked, and failing that theCARGO_TARGET_DIRenvironment variable is checked, and failing that the rootpackage's directory joined with the directory name "target" is used.
There are a few caveats to switching target directories, however:
not called "target", then Cargo may walk the output directory when determining
whether a tree is fresh.
currently for
Cargo.tomlfiles to learn about local packages.exascerbated because many Cargo projects can share the same output directory.
built into directory
fooand then that crate is later used as a dependency,it will be recompiled.
The naming limitations can be overcome in time, but for now it greatly
simplifies the crawling routines and shouldn't have much of a negative impact
other than some Cargo runtimes (which can in turn be negated by following the
"target" name convention).
Closes #482