MinSizeRel

MinSizeRel stands for minimum size release and is one of the standard build configurations provided by CMake. It designates a release-style build that prioritizes small binary size over execution speed. This configuration is commonly used when minimizing the footprint of a produced artifact is more important than raw performance, such as in embedded deployment or distribution packaging.

When you configure a project with CMake, you select MinSizeRel as the build type by setting CMAKE_BUILD_TYPE to MinSizeRel (for single-configuration generators) or by choosing the corresponding configuration in a multi-config generator such as Visual Studio. The exact compiler and linker flags used for MinSizeRel are supplied by the toolchain, but they generally enable size-focused optimizations (for example, -Os or -Oz on GCC/Clang and /O1 on MSVC) and minimize or omit debug information relative to other release modes.

MinSizeRel is distinct from Release, which emphasizes performance, and RelWithDebInfo, which balances speed with debugging information. Compared with Debug, MinSizeRel typically uses optimizations with a clear focus on shrinking code size, at the potential cost of some transparency during debugging.

Users can further customize the flags for this configuration by setting the language-specific variables CMAKE_C_FLAGS_MINSIZEREL and CMAKE_CXX_FLAGS_MINSIZEREL (and their linker counterparts) if the default settings do not meet their needs.