cargo check

NAME

cargo-check - Check the current package

SYNOPSIS

cargo check [OPTIONS]

DESCRIPTION

Check a local package and all of its dependencies for errors. This willessentially compile the packages without performing the final step of codegeneration, which is faster than running cargo build. The compiler will savemetadata files to disk so that future runs will reuse them if the source hasnot been modified.

OPTIONS

Package Selection

By default, when no package selection options are given, the packages selecteddepend 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 thenthe workspaces default members are selected, otherwise only the package definedby the manifest will be selected.

The default members of a workspace can be set explicitly with theworkspace.default-members key in the root manifest. If this is not set, avirtual workspace will include all workspace members (equivalent to passing—workspace), and a non-virtual workspace will include only the root crate itself.

  • -pSPEC…​
  • —packageSPEC…​

  • Check only the specified packages. See cargo-pkgid(1) for theSPEC format. This flag may be specified multiple times.

  • —workspace

  • Check all members in the workspace.

  • —all

  • Deprecated alias for —workspace.

  • —excludeSPEC…​

  • Exclude the specified packages. Must be used in conjunction with the—workspace flag. This flag may be specified multiple times.

Target Selection

When no target selection options are given, cargo check will check allbinary and library targets of the selected packages. Binaries are skipped ifthey have required-features that are missing.

Passing target selection flags will check only thespecified targets.

  • —lib

  • Check the package’s library.

  • —binNAME…​

  • Check the specified binary. This flag may be specified multiple times.

  • —bins

  • Check all binary targets.

  • —exampleNAME…​

  • Check the specified example. This flag may be specified multiple times.

  • —examples

  • Check all example targets.

  • —testNAME…​

  • Check the specified integration test. This flag may be specified multipletimes.

  • —tests

  • Check all targets in test mode that have the test = true manifestflag set. By default this includes the library and binaries built asunittests, and integration tests. Be aware that this will also build anyrequired dependencies, so the lib target may be built twice (once as aunittest, and once as a dependency for binaries, integration tests, etc.).Targets may be enabled or disabled by setting the test flag in themanifest settings for the target.

  • —benchNAME…​

  • Check the specified benchmark. This flag may be specified multiple times.

  • —benches

  • Check all targets in benchmark mode that have the bench = truemanifest flag set. By default this includes the library and binaries builtas benchmarks, and bench targets. Be aware that this will also build anyrequired dependencies, so the lib target may be built twice (once as abenchmark, and once as a dependency for binaries, benchmarks, etc.).Targets may be enabled or disabled by setting the bench flag in themanifest settings for the target.

  • —all-targets

  • Check all targets. This is equivalent to specifying —lib —bins—tests —benches —examples.

Feature Selection

When no feature options are given, the default feature is activated forevery selected package.

  • —featuresFEATURES

  • Space or comma separated list of features to activate. These features onlyapply to the current directory’s package. Features of direct dependenciesmay be enabled with <dep-name>/<feature-name> syntax.

  • —all-features

  • Activate all available features of all selected packages.

  • —no-default-features

  • Do not activate the default feature of the current directory’spackage.

Compilation Options

  • —targetTRIPLE
  • Check for the given architecture. The default is the hostarchitecture. The general format of the triple is<arch><sub>-<vendor>-<sys>-<abi>. Run rustc —print target-list for alist of supported targets.

This may also be specified with the build.targetconfig value.

  • —release

  • Check optimized artifacts with the release profile. See thePROFILES section for details on how this affects profile selection.

  • —profileNAME

  • Changes check behavior. Currently only test issupported, which will check with the#[cfg(test)] attribute enabled. This is useful to have itcheck unit tests which are usually excluded viathe cfg attribute. This does not change the actual profile used.

Output Options

  • —target-dirDIRECTORY
  • Directory for all generated artifacts and intermediate files. May also bespecified with the CARGO_TARGET_DIR environment variable, or thebuild.target-dir config value. Defaultsto target in the root of the workspace.

Display Options

  • -v
  • —verbose

  • Use verbose output. May be specified twice for "very verbose" output whichincludes extra output such as dependency warnings and build script output.May also be specified with the term.verboseconfig value.

  • -q

  • —quiet

  • No output printed to stdout.

  • —colorWHEN

  • Control when colored output is used. Valid values:

  • auto (default): Automatically detect if color support is available on theterminal.

  • always: Always display colors.

  • never: Never display colors.

May also be specified with the term.colorconfig value.

  • —message-formatFMT
  • The output format for diagnostic messages. Can be specified multiple timesand 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.

  • json-diagnostic-short: Ensure the rendered field of JSON messages containsthe "short" rendering from rustc.

  • json-diagnostic-rendered-ansi: Ensure the rendered field of JSON messagescontains embedded ANSI color codes for respecting rustc’s default colorscheme.

  • json-render-diagnostics: Instruct Cargo to not include rustc diagnostics inin JSON messages printed, but instead Cargo itself should render theJSON diagnostics coming from rustc. Cargo’s own JSON diagnostics and otherscoming from rustc are still emitted.

Manifest Options

  • —manifest-pathPATH

  • Path to the Cargo.toml file. By default, Cargo searches in the currentdirectory or any parent directory for the Cargo.toml file.

  • —frozen

  • —locked
  • Either of these flags requires that the Cargo.lock file isup-to-date. If the lock file is missing, or it needs to be updated, Cargo willexit with an error. The —frozen flag also prevents Cargo fromattempting to access the network to determine if it is out-of-date.

These may be used in environments where you want to assert that theCargo.lock file is up-to-date (such as a CI build) or want to avoid networkaccess.

  • —offline
  • Prevents Cargo from accessing the network for any reason. Without thisflag, Cargo will stop with an error if it needs to access the network andthe network is not available. With this flag, Cargo will attempt toproceed without the network if possible.

Beware that this may result in different dependency resolution than onlinemode. Cargo will restrict itself to crates that are downloaded locally, evenif 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 goingoffline.

May also be specified with the net.offline config value.

Common Options

  • -h
  • —help

  • Prints help information.

  • -ZFLAG…​

  • Unstable (nightly-only) flags to Cargo. Run cargo -Z help fordetails.

Miscellaneous Options

  • -jN
  • —jobsN
  • Number of parallel jobs to run. May also be specified with thebuild.jobs config value. Defaults tothe number of CPUs.

PROFILES

Profiles may be used to configure compiler options such as optimization levelsand debug settings. Seethe referencefor more details.

Profile selection depends on the target and crate being built. By default thedev or test profiles are used. If the —release flag is given, then therelease or bench profiles are used.

TargetDefault Profile—release Profile
lib, bin, exampledevrelease
test, bench, or any target in "test" or "bench" modetestbench

Dependencies use the dev/release profiles.

ENVIRONMENT

See the reference fordetails on environment variables that Cargo reads.

Exit Status

  • 0

  • Cargo succeeded.

  • 101

  • Cargo failed to complete.

EXAMPLES

  • Check the local package for errors:
  1. cargo check
  • Check all targets, including unit tests:
  1. cargo check --all-targets --profile=test

SEE ALSO

cargo(1), cargo-build(1)