CMAKE_CXX_EXTENSIONS

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Cmake/docs/3.21/variable/cmake cxx extensions


CMAKE_CXX_EXTENSIONS

New in version 3.1.


Default value for CXX_EXTENSIONS property of targets.

This variable is used to initialize the CXX_EXTENSIONS property on all targets. See that target property for additional information.

See the cmake-compile-features(7) manual for information on compile features and a list of supported compilers.

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https://cmake.org/cmake/help/v3.21/variable/CMAKE_CXX_EXTENSIONS.html