cargo build

NAME

cargo-build - Compile the current package

SYNOPSIS

cargo build [OPTIONS]

DESCRIPTION

Compile local packages and all of their dependencies.

OPTIONS

Package Selection

By default, when no package selection options are given, the packages selected depend on the current working directory. In the root of a virtual workspace, all workspace members are selected (--all is implied). Otherwise, only the package in the current directory will be selected. The default packages may be overridden with the workspace.default-members key in the root Cargo.toml manifest.

-p SPEC…​
--package SPEC…​

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

--all

Build all members in the workspace.

--exclude SPEC…​

Exclude the specified packages. Must be used in conjunction with the --all flag. This flag may be specified multiple times.

Target Selection

When no target selection options are given, cargo build will build all binary and library targets of the selected packages. Binaries are skipped if they have required-features that are missing.

Passing target selection flags will build only the specified targets.

--lib

Build the package’s library.

--bin NAME…​

Build the specified binary. This flag may be specified multiple times.

--bins

Build all binary targets.

--example NAME…​

Build the specified example. This flag may be specified multiple times.

--examples

Build all example targets.

--test NAME…​

Build the specified integration test. This flag may be specified multiple times.

--tests

Build all tests. This includes both unit tests for libraries and binaries and integration tests. Targets may be disabled by setting test = false in the manifest settings for the target. Targets (such as examples) may be explicitly included by setting test = true in the target settings.

--bench NAME…​

Build the specified benchmark. This flag may be specified multiple times.

--benches

Build all benchmarks. This includes both unit benchmarks for libraries and binaries and bench targets. Targets may be disabled by setting bench = false in the manifest settings for the target. Targets (such as examples) may be explicitly included by setting bench = true in the target settings.

--all-targets

Build all targets.

Feature Selection

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

--features FEATURES

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.

--all-features

Activate all available features of all selected packages.

--no-default-features

Do not activate the default feature of the current directory’s package.

Compilation Options

--target TRIPLE

Build for the given architecture. The default is the host architecture.

The general format of the triple is <arch><sub>-<vendor>-<sys>-<abi> where:

  • arch = The base CPU architecture, for example x86_64, i686, arm, thumb, mips, etc.

  • sub = The CPU sub-architecture, for example arm has v7, v7s, v5te, etc.

  • vendor = The vendor, for example unknown, apple, pc, linux, etc.

  • sys = The system name, for example linux, windows, etc. none is typically used for bare-metal without an OS.

  • abi = The ABI, for example gnu, android, eabi, etc.

Some parameters may be omitted. Run rustc --print target-list for a list of supported targets.

This may also be specified with the build.target config value.

--release

Build artifacts in release mode, with optimizations. See the PROFILES section for details on how this affects profile selection.

Output Options

--target-dir DIRECTORY

Directory for all generated artifacts and intermediate files. May also be specified with the CARGO_TARGET_DIR environment variable, or the build.target-dir config value. Defaults to target in the root of the workspace.

--out-dir DIRECTORY

Copy final artifacts to this directory.

This option is unstable and available only on the nightly channel and requires the -Z unstable-options flag to enable.

Display Options

-v
--verbose

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 term.verbose config value.

-q
--quiet

No output printed to stdout.

--color WHEN

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 term.color config value.

--message-format FMT

The output format for diagnostic messages. Valid values:

  • human (default): Display in a human-readable text format.

  • json: Emit JSON messages to stdout.

  • short: Emit shorter, human-readable text messages.

--build-plan

Outputs a series of JSON messages to stdout that indicate the commands to run the build.

This option is unstable and available only on the nightly channel and requires the -Z unstable-options flag to enable.

Manifest Options

--manifest-path PATH

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

--frozen
--locked

Either of these flags requires that the Cargo.lock file is up-to-date. If the lock file is missing, or it needs to be updated, Cargo will exit with an error. The --frozen flag 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.lock file is up-to-date (such as a CI build) or want to avoid network access.

Common Options

-h
--help

Prints help information.

-Z FLAG…​

Unstable (nightly-only) flags to Cargo. Run cargo -Z help for details.

Miscellaneous Options

-j N
--jobs N

Number of parallel jobs to run. May also be specified with the build.jobs config value. Defaults to the number of CPUs.

PROFILES

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 dev or test profiles are used. If the --release flag is given, then the release or bench profiles are used.

Target Default Profile --release Profile

lib, bin, example

dev

release

test, bench

test

bench

Dependencies use the dev/release profiles.

ENVIRONMENT

See the reference for details on environment variables that Cargo reads.

Exit Status

0

Cargo succeeded.

101

Cargo failed to complete.

EXAMPLES

  1. Build the local package and all of its dependencies:

    cargo build
  2. Build with optimizations:

    cargo build --release