[CMake] Allow version overrides with -DLLDB_VERSION_MAJOR/MINOR/PATCH/SUFFIX

[sgraenitz]

Summary

This follows the approach in Clang. If no overrides are given, LLDB_VERSION_* is inferred from LLVM_VERSION_*. This mimics the current behaviour (PACKAGE_VERSION itself is generated from LLVM_VERSION_*).
For in-tree builds LLVM_VERSION_* will be defined at this point already. For standalone builds, LLDBConfig.cmake is included after LLDBStandalone.cmake which includes LLVMConfig.cmake.

[aprantl]

Seems reasonable!

[xiaobai]

Yep, this looks good to me. Thanks! :)

[clayborg]

nice!

CMakeLists.txt

if (NOT APPLE)
     message(FATAL_ERROR "LLDB.framework can only be generated when targeting Apple platforms")
   endif()
 
   add_custom_target(lldb-framework)
   # These are used to fill out LLDB-Info.plist. These are relevant when building
   # the framework, and must be defined before building liblldb.
   set(PRODUCT_NAME "LLDB")
   set(EXECUTABLE_NAME "LLDB")
-  set(CURRENT_PROJECT_VERSION "360.99.0")
+  set(CURRENT_PROJECT_VERSION "${LLDB_VERSION}")
   set(LLDB_SUITE_TARGET lldb-framework)
 
   set(LLDB_FRAMEWORK_DIR
     ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/${LLDB_FRAMEWORK_INSTALL_DIR})
   include(LLDBFramework)
 endif()
 
 add_subdirectory(docs)

cmake/modules/LLDBConfig.cmake

 if (CMAKE_SOURCE_DIR STREQUAL CMAKE_BINARY_DIR)
   message(FATAL_ERROR "In-source builds are not allowed. CMake would overwrite "
 "the makefiles distributed with LLDB. Please create a directory and run cmake "
 "from there, passing the path to this source directory as the last argument. "
 "This process created the file `CMakeCache.txt' and the directory "
 "`CMakeFiles'. Please delete them.")
 endif()
 
-# Compute the LLDB version from the LLVM version.
-string(REGEX MATCH "[0-9]+\\.[0-9]+(\\.[0-9]+)?" LLDB_VERSION
-  ${PACKAGE_VERSION})
+# If LLDB_VERSION_* is specified, use it, if not use LLVM_VERSION_*.
+if(NOT DEFINED LLDB_VERSION_MAJOR)
+  set(LLDB_VERSION_MAJOR ${LLVM_VERSION_MAJOR})
+endif()
+if(NOT DEFINED LLDB_VERSION_MINOR)
+  set(LLDB_VERSION_MINOR ${LLVM_VERSION_MINOR})
+endif()
+if(NOT DEFINED LLDB_VERSION_PATCH)
+  set(LLDB_VERSION_PATCH ${LLVM_VERSION_PATCH})
+endif()
+if(NOT DEFINED LLDB_VERSION_SUFFIX)
+  set(LLDB_VERSION_SUFFIX ${LLVM_VERSION_SUFFIX})
+endif()
+set(LLDB_VERSION "${LLDB_VERSION_MAJOR}.${LLDB_VERSION_MINOR}.${LLDB_VERSION_PATCH}${LLDB_VERSION_SUFFIX}")
 message(STATUS "LLDB version: ${LLDB_VERSION}")
 
 include_directories(BEFORE
   ${CMAKE_CURRENT_SOURCE_DIR}/include
   ${CMAKE_CURRENT_BINARY_DIR}/include
   )
 
 if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY)