Platform Rules

constraint_setting

constraint_setting(name, default_constraint_value, deprecation, distribs, features, licenses, tags, testonly, visibility)

This rule defines a type of constraint that can be used to define an execution platform.

Arguments

Attributes
name	Name; required A unique name for this rule.
default_constraint_value	Name; optional The label of the default value for the setting, to be used if no value is given. The default value must be in the same package as the setting itself.

constraint_value

constraint_value(name, constraint_setting, deprecation, distribs, features, licenses, tags, testonly, visibility)

This rule defines a specific value of a constraint, which can be used to define execution platforms.

Arguments

Attributes
name	Name; required A unique name for this rule.
constraint_setting	Label; required The constraint_setting rule this value is applied to.

platform

platform(name, constraint_values, deprecation, distribs, features, licenses, remote_execution_properties, tags, testonly, visibility)

This rule defines a platform, as a collection of constraint_values.

Examples

This defines two possible platforms, each targeting a different CPU type.

constraint_setting(name="cpu")
constraint_value(
    name="arm64",
    constraint_setting=":cpu")
constraint_value(
    name="k8",
    constraint_setting=":cpu")
platform(
    name="mobile_device",
    constraint_values = [
        ":arm64",
    ])
platform(
    name="devel",
    constraint_values = [
        ":k8",
    ])

Arguments

Attributes
name	Name; required A unique name for this rule.
constraint_values	List of labels; optional The constraint_values that define this platform.
remote_execution_properties	String; optional A string used to configure a remote execution platform. Actual builds make no attempt to interpret this, it is treated as opaque data that can be used by a specific SpawnRunner.

toolchain

toolchain(name, deprecation, distribs, exec_compatible_with, features, licenses, tags, target_compatible_with, testonly, toolchain, toolchain_type, visibility)

This rule declares a specific toolchain's type and constraints so that it can be selected during toolchain resolution.

Arguments

Attributes
name	Name; required A unique name for this rule.
exec_compatible_with	List of labels; optional; nonconfigurable The constraints, as defined by constraint_value() and constraint_setting(), that are required on the execution platform for this toolchain to be selected.
target_compatible_with	List of labels; optional; nonconfigurable The constraints, as defined by constraint_value() and constraint_setting(), that are required on the target platform for this toolchain to be selected.
toolchain	Name; required; nonconfigurable The label of the actual toolchain data to be used when this toolchain is selected.
toolchain_type	Name; required; nonconfigurable The type of the toolchain, which should be the label of a toolchain_type() target.