CMP0049 ------- Do not expand variables in target source entries. CMake 2.8.12 and lower performed an extra layer of variable expansion when evaluating source file names:: set(a_source foo.c) add_executable(foo \${a_source}) .. note: no cmake highlighting since this syntax is deprecated This was undocumented behavior. The ``OLD`` behavior for this policy is to expand such variables when processing the target sources. The ``NEW`` behavior for this policy is to issue an error if such variables need to be expanded. .. |INTRODUCED_IN_CMAKE_VERSION| replace:: 3.0 .. |WARNS_OR_DOES_NOT_WARN| replace:: warns .. include:: STANDARD_ADVICE.txt .. include:: DEPRECATED.txt