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CMP0083

Help/policy/CMP0083.rst

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CMP0083

.. versionadded:: 3.14

To control generation of Position Independent Executable (PIE) or not, some flags are required at link time.

CMake 3.13 and lower did not add these link flags when :prop_tgt:POSITION_INDEPENDENT_CODE is set.

The OLD behavior for this policy is to not manage PIE link flags. The NEW behavior is to add link flags if :prop_tgt:POSITION_INDEPENDENT_CODE is set:

  • Set to TRUE: flags to produce a position independent executable are passed to the linker step. For example -pie for GCC.
  • Set to FALSE: flags not to produce a position independent executable are passed to the linker step. For example -no-pie for GCC.
  • Not set: no flags are passed to the linker step.

Since a given linker may not support PIE flags in all environments in which it is used, it is the project's responsibility to use the :module:CheckPIESupported module to check for support to ensure that the :prop_tgt:POSITION_INDEPENDENT_CODE target property for executables will be honored at link time.

.. |INTRODUCED_IN_CMAKE_VERSION| replace:: 3.14 .. |WARNS_OR_DOES_NOT_WARN| replace:: does not warn .. include:: include/STANDARD_ADVICE.rst

.. Note::

Android platform has a special handling of PIE so it is not required to use the :module:CheckPIESupported module to ensure flags are passed to the linker.

.. include:: include/DEPRECATED.rst

Examples ^^^^^^^^

Behave like CMake 3.13 and do not apply any PIE flags at link stage.

.. code-block:: cmake

cmake_minimum_required(VERSION 3.13) project(foo)

...

add_executable(foo ...) set_property(TARGET foo PROPERTY POSITION_INDEPENDENT_CODE TRUE)

Use the :module:CheckPIESupported module to detect whether PIE is supported by the current linker and environment. Apply PIE flags only if the linker supports them.

.. code-block:: cmake

cmake_minimum_required(VERSION 3.14) # CMP0083 NEW project(foo)

include(CheckPIESupported) check_pie_supported()

...

add_executable(foo ...) set_property(TARGET foo PROPERTY POSITION_INDEPENDENT_CODE TRUE)