The docs for [`CMAKE_<CONFIG>_POSTFIX`](https://cmake.org/cmake/help/latest/variable/CMAKE_CONFIG_POSTFIX.html) say: > Default filename postfix for libraries under configuration `<CONFIG>`. > > When a _**non-executable target**_ is created its `<CONFIG>_POSTFIX` target property is initialized with the value of this variable if it is set. But [the tutorial on "Packaging Release and Debug"](https://cmake.org/cmake/help/latest/guide/tutorial/Packaging%20Debug%20and%20Release.html) says: > By default, CMake's model is that a build directory only contains a single configuration, be it Debug, Release, MinSizeRel, or RelWithDebInfo. It is possible, however, to setup CPack to bundle multiple build directories and construct a package that contains multiple configurations of the same project. > > First, we want to ensure that the debug and release builds use different names for the _**executables and**_ libraries that will be installed. Let's use d as the postfix for the _**debug executable and**_ libraries. > > Set [`CMAKE_DEBUG_POSTFIX`](https://cmake.org/cmake/help/latest/variable/CMAKE_DEBUG_POSTFIX.html#variable:CMAKE_DEBUG_POSTFIX) near the beginning of the top-level CMakeLists.txt file: > > \[...\] So which is it? Does it use the postfix for executables or not? I did a quick test on Ubuntu with Unix Makefiles and it doesn't use the postfix for executables. Is it different for other generators / host systems?