qtp0003.qdoc

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// Copyright (C) 2024 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
 
/*!
\page qt-cmake-policy-qtp0003.html
\ingroup qt-cmake-policies
\since 6.7
\title QTP0003
\keyword qt_cmake_policy_qtp0003
 
\summary {Consider the BUILD_SHARED_LIBS value when creating Qt libraries.}
 
This policy was introduced in Qt 6.7. The policy affects the default type of the
libraries created using \l {CMake Commands in Qt6 Core}{Qt CMake API}, like
\l {qt_add_library}, \l{qt_add_plugin}, \l{qt_add_qml_module}.
 
If the policy is set to \c OLD, the default library type that is selected is
aligned with the Qt build type, either \c shared or \c static.
 
If the policy is set to \c NEW, the library type is selected according to the
\l {CMake BUILD_SHARED_LIBS Documentation}{BUILD_SHARED_LIBS} value if it's set.
If \c BUILD_SHARED_LIBS is not set, the default library type falls back to the
Qt build type.
 
For example, the following code will use the Qt build type as the default
library type for the \c MyLib target, despite the fact \c BUILD_SHARED_LIBS is
set to \c ON:
\badcode
set(BUILD_SHARED_LIBS ON)
...
qt6_add_library(MyLib sourcefile.h sourcefile.cpp)
\endcode
 
If you set the QTP0003 to \c NEW before the \l {qt6_add_library}{qt_add_library}
call, \c BUILD_SHARED_LIBS will affect the library default type and \c MyLib
will be the shared library.
\badcode
set(BUILD_SHARED_LIBS ON)
...
qt_policy(SET QTP0003 NEW)
qt6_add_library(MyLib sourcefile.h sourcefile.cpp)
\endcode
 
\sa qt_policy, {Qt CMake policies}, qt_add_library
 
*/