CMAKESYSROOT

CMAKESYSROOT is a CMake variable that specifies the system root directory. This variable is primarily used in cross-compilation scenarios where the target system's libraries, headers, and other build artifacts are located in a directory different from the host system's standard locations.

When CMake is configured to use a system root, it will prepend this path to all compiler and linker searches for system-provided files. This ensures that the build process utilizes the correct toolchain and dependencies for the target platform, rather than the host's. For example, if CMAKESYSROOT is set to "/path/to/target/sysroot", CMake will look for files like "stdio.h" or "libc.so" within "/path/to/target/sysroot/usr/include" and "/path/to/target/sysroot/usr/lib", respectively.

Setting CMAKESYSROOT is a common practice when building embedded systems or when targeting different architectures on the same host machine. It allows developers to maintain a consistent build environment for a specific target without polluting the host system's global installation paths. The variable can be set on the CMake command line using `-DCMAKE_SYSROOT=/path/to/target/sysroot` or within a CMakeLists.txt file. It is crucial for CMake to correctly locate all necessary system files for the target environment to succeed.

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