CMAKE__FLAGS_DEBUG_INIT
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Cmake/docs/3.21/variable/cmake lang flags debug init
CMAKE__FLAGS_DEBUG_INIT
New in version 3.7.
This variable is the Debug
variant of the CMAKE__FLAGS__INIT variable.
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Licensed under the BSD 3-clause License.
https://cmake.org/cmake/help/v3.21/variable/CMAKE_LANG_FLAGS_DEBUG_INIT.html