[CMake] Move project() call to main CMake file

[hhb]

Summary

The main CMake file don't have a project() call. In this case, cmake will run a dummy project(Project ) at the very beginning. Even before cmake_minimum_required. And a series of compiler detections will be triggered.

This is problematic if we depends on some policy to be set. E.g. CMP0056. try_compile will fail before we have a chance to do anything.

lldb/trunk/CMakeLists.txt

 cmake_minimum_required(VERSION 3.4.3)
 
 if(POLICY CMP0075)
   cmake_policy(SET CMP0075 NEW)
 endif()
 
 # Add path for custom modules.
 set(CMAKE_MODULE_PATH
   ${CMAKE_MODULE_PATH}
   "${CMAKE_CURRENT_SOURCE_DIR}/cmake"
   "${CMAKE_CURRENT_SOURCE_DIR}/cmake/modules"
   )
 
 # If we are not building as part of LLVM, build LLDB as a standalone project,
 # using LLVM as an external library.
 if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
+  project(lldb)
   include(LLDBStandalone)
 endif()
 
 include(LLDBConfig)
 include(AddLLDB)
 
 # Define the LLDB_CONFIGURATION_xxx matching the build type.
 if( uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" )

lldb/trunk/cmake/modules/LLDBStandalone.cmake

-project(lldb)
-
 option(LLVM_INSTALL_TOOLCHAIN_ONLY "Only include toolchain files in the 'install' target." OFF)
 
 find_package(LLVM REQUIRED CONFIG HINTS "${LLVM_DIR}" NO_CMAKE_FIND_ROOT_PATH)
 find_package(Clang REQUIRED CONFIG HINTS "${Clang_DIR}" NO_CMAKE_FIND_ROOT_PATH)
 
 # We set LLVM_CMAKE_PATH so that GetSVN.cmake is found correctly when building SVNVersion.inc
 set(LLVM_CMAKE_PATH ${LLVM_CMAKE_DIR} CACHE PATH "Path to LLVM CMake modules")