cargo-check - Check the current package
cargo check [options]
Check a local package and all of its dependencies for errors. This will
essentially compile the packages without performing the final step of code
generation, which is faster than running
cargo build. The compiler will save
metadata files to disk so that future runs will reuse them if the source has
not been modified. Some diagnostics and errors are only emitted during code
generation, so they inherently won't be reported with
By default, when no package selection options are given, the packages selected
depend on the selected manifest file (based on the current working directory if
--manifest-path is not given). If the manifest is the root of a workspace then
the workspaces default members are selected, otherwise only the package defined
by the manifest will be selected.
The default members of a workspace can be set explicitly with the
workspace.default-members key in the root manifest. If this is not set, a
virtual workspace will include all workspace members (equivalent to passing
--workspace), and a non-virtual workspace will include only the root crate itself.
- Check only the specified packages. See cargo-pkgid(1) for the SPEC format. This flag may be specified multiple times.
- Check all members in the workspace.
- Deprecated alias for
- Exclude the specified packages. Must be used in conjunction with the
--workspaceflag. This flag may be specified multiple times.
When no target selection options are given,
cargo check will check all
binary and library targets of the selected packages. Binaries are skipped if
required-features that are missing.
Passing target selection flags will check only the specified targets.
- Check the package's library.
- Check the specified binary. This flag may be specified multiple times.
- Check all binary targets.
- Check the specified example. This flag may be specified multiple times.
- Check all example targets.
- Check the specified integration test. This flag may be specified multiple times.
- Check all targets in test mode that have the
test = truemanifest flag set. By default this includes the library and binaries built as unittests, and integration tests. Be aware that this will also build any required dependencies, so the lib target may be built twice (once as a unittest, and once as a dependency for binaries, integration tests, etc.). Targets may be enabled or disabled by setting the
testflag in the manifest settings for the target.
- Check the specified benchmark. This flag may be specified multiple times.
- Check all targets in benchmark mode that have the
bench = truemanifest flag set. By default this includes the library and binaries built as benchmarks, and bench targets. Be aware that this will also build any required dependencies, so the lib target may be built twice (once as a benchmark, and once as a dependency for binaries, benchmarks, etc.). Targets may be enabled or disabled by setting the
benchflag in the manifest settings for the target.
- Check all targets. This is equivalent to specifying
--lib --bins --tests --benches --examples.
The feature flags allow you to control the enabled features for the "current"
package. The "current" package is the package in the current directory, or the
one specified in
--manifest-path. If running in the root of a virtual
workspace, then the default features are selected for all workspace members,
or all features if
--all-features is specified.
When no feature options are given, the
default feature is activated for
every selected package.
- Space or comma separated list of features to activate. These features only
apply to the current directory's package. Features of direct dependencies
may be enabled with
<dep-name>/<feature-name>syntax. This flag may be specified multiple times, which enables all specified features.
- Activate all available features of all selected packages.
- Do not activate the
defaultfeature of the current directory's package.
- Check for the given architecture. The default is the host
architecture. The general format of the triple is
rustc --print target-listfor a list of supported targets.
This may also be specified with the
Note that specifying this flag makes Cargo run in a different mode where the target artifacts are placed in a separate directory. See the build cache documentation for more details.
- Check optimized artifacts with the
releaseprofile. See the PROFILES section for details on how this affects profile selection.
- Changes check behavior. Currently only
testis supported, which will check with the
#[cfg(test)]attribute enabled. This is useful to have it check unit tests which are usually excluded via the
cfgattribute. This does not change the actual profile used.
- Directory for all generated artifacts and intermediate files. May also be
specified with the
CARGO_TARGET_DIRenvironment variable, or the
build.target-dirconfig value. Defaults to
targetin the root of the workspace.
- Use verbose output. May be specified twice for "very verbose" output which
includes extra output such as dependency warnings and build script output.
May also be specified with the
- No output printed to stdout.
- Control when colored output is used. Valid values:
auto(default): Automatically detect if color support is available on the terminal.
always: Always display colors.
never: Never display colors.
May also be specified with the
- The output format for diagnostic messages. Can be specified multiple times
and consists of comma-separated values. Valid values:
human(default): Display in a human-readable text format.
short: Emit shorter, human-readable text messages.
json: Emit JSON messages to stdout. See the reference for more details.
json-diagnostic-short: Ensure the
renderedfield of JSON messages contains the "short" rendering from rustc.
json-diagnostic-rendered-ansi: Ensure the
renderedfield of JSON messages contains embedded ANSI color codes for respecting rustc's default color scheme.
json-render-diagnostics: Instruct Cargo to not include rustc diagnostics in in JSON messages printed, but instead Cargo itself should render the JSON diagnostics coming from rustc. Cargo's own JSON diagnostics and others coming from rustc are still emitted.
- Path to the
Cargo.tomlfile. By default, Cargo searches for the
Cargo.tomlfile in the current directory or any parent directory.
- Either of these flags requires that the
Cargo.lockfile is up-to-date. If the lock file is missing, or it needs to be updated, Cargo will exit with an error. The
--frozenflag also prevents Cargo from attempting to access the network to determine if it is out-of-date.
These may be used in environments where you want to assert that the
Cargo.lockfile is up-to-date (such as a CI build) or want to avoid network access.
- Prevents Cargo from accessing the network for any reason. Without this
flag, Cargo will stop with an error if it needs to access the network and
the network is not available. With this flag, Cargo will attempt to
proceed without the network if possible.
Beware that this may result in different dependency resolution than online mode. Cargo will restrict itself to crates that are downloaded locally, even if there might be a newer version as indicated in the local copy of the index. See the cargo-fetch(1) command to download dependencies before going offline.
May also be specified with the
- If Cargo has been installed with rustup, and the first argument to
+, it will be interpreted as a rustup toolchain name (such as
+nightly). See the rustup documentation for more information about how toolchain overrides work.
- Prints help information.
- Unstable (nightly-only) flags to Cargo. Run
cargo -Z helpfor details.
- Number of parallel jobs to run. May also be specified with the
build.jobsconfig value. Defaults to the number of CPUs.
Profiles may be used to configure compiler options such as optimization levels and debug settings. See the reference for more details.
Profile selection depends on the target and crate being built. By default the
test profiles are used. If the
--release flag is given, then the
bench profiles are used.
|lib, bin, example|
|test, bench, or any target in "test" or "bench" mode|
Dependencies use the
See the reference for details on environment variables that Cargo reads.
0: Cargo succeeded.
101: Cargo failed to complete.
Check the local package for errors:
Check all targets, including unit tests:
cargo check --all-targets --profile=test