llvm/cmake/Modules/LLVMVersion.cmake

# The LLVM Version number information

if(NOT DEFINED LLVM_VERSION_MAJOR)
  set(LLVM_VERSION_MAJOR 20)
endif()
if(NOT DEFINED LLVM_VERSION_MINOR)
  set(LLVM_VERSION_MINOR 0)
endif()
if(NOT DEFINED LLVM_VERSION_PATCH)
  set(LLVM_VERSION_PATCH 0)
endif()
if(NOT DEFINED LLVM_VERSION_SUFFIX)
  set(LLVM_VERSION_SUFFIX git)
endif()