cmake LIBCXX_HAS_MUSL_LIBC examples

Lewuathe/mlir-hello thirdparty/llvm-project/libcxx/CMakeLists.txt :295 

option(LIBCXX_HAS_MUSL_LIBC "Build libc++ with support for the Musl C library" OFF)

PlatONnetwork/pWASM libc++/libcxx/CMakeLists.txt :200 

option(LIBCXX_HAS_MUSL_LIBC "Build libc++ with support for the Musl C library" OFF)

PlatONnetwork/pWASM libc++/libcxx/CMakeLists.txt :336 

message(FATAL_ERROR "LIBCXX_INSTALL_SUPPORT_HEADERS can not be turned off"
                      "when building for Musl with LIBCXX_HAS_MUSL_LIBC.")

CTSRD-CHERI/cheribsd contrib/subrepo-cheri-libc++/CMakeLists.txt :269 

option(LIBCXX_HAS_MUSL_LIBC "Build libc++ with support for the Musl C library" OFF)