<p>
<code>List of <a href="../build-ref.html#labels">labels</a>; optional</code>
</p>

<p>
A list of
<code><a href="platform.html#constraint_value">constraint_value</a></code>s
that must be present in the target platform for this target to be considered
<em>compatible</em>. This is in addition to any constraints already set by the
rule type. If the target platform does not satisfy all listed constraints then
the target is considered <em>incompatible</em>. Incompatible targets are
skipped for building and testing when the target pattern is expanded
(e.g. `//...`, `:all`). When explicitly specified on the command line,
incompatible targets cause Bazel to print an error and cause a build or test
failure.
</p>

<p>
Targets that transitively depend on incompatible targets are themselves
considered incompatible. They are also skipped for building and testing.
</p>

<p>
An empty list (which is the default) signifies that the target is compatible
with all platforms.
<p>

<p>
See the
<a href="../platforms.html#skipping-incompatible-targets">Platforms</a>
page for more information about incompatible target skipping.
</p>
