qt_policy

Modify the default behavior of Qt's CMake API.

The command is defined in the Core component of the Qt6 package, which can be loaded like so:

 find_package(Qt6 REQUIRED COMPONENTS Core)

This command was introduced in Qt 6.5.

Synopsis

 qt_policy(
     [SET policy behavior]
     [GET policy variable]
 )

If versionless commands are disabled, use qt6_policy() instead. It supports the same set of arguments as this command.

Description

This command has two modes:

  • When the SET keyword is used, this command can be used to opt in to behavior changes in Qt's CMake API, or to explicitly opt out of them.
  • When the GET keyword is used, variable is set to the current value for the policy.

policyname must be the name of a Qt cmake policy. Using an unknown policy is an error; code supporting older Qt versions should check with

 if(QT_KNOWN_POLICY_<policy_name>)

whether the policy exists before querying or setting it.

behavior can either be

  • NEW to opt into the new behavior, or
  • OLD to explicitly opt-out of it.

See also qt_standard_project_setup.