[CMake] Export CMAKE_CONFIGURATION_TYPES for the LLVM build-tree

[sgraenitz]

Summary

Useful info for standalone builds of subprojects. If a multi-configuration generator was used for the provided LLVM build-tree, standalone builds should consider actual subdirectories per configuration in find_program() (e.g. looking for llvm-lit or llvm-tblgen).

[sgraenitz]

That will be fine with post-commit review. Will submit tomorrow.

llvm/cmake/modules/LLVMConfig.cmake.in

 set(LLVM_LIBRARY_DIR "@LLVM_CONFIG_LIBRARY_DIRS@")
 
 set(LLVM_DEFINITIONS "@LLVM_DEFINITIONS@")
 set(LLVM_CMAKE_DIR "@LLVM_CONFIG_CMAKE_DIR@")
 set(LLVM_BINARY_DIR "@LLVM_CONFIG_BINARY_DIR@")
 set(LLVM_TOOLS_BINARY_DIR "@LLVM_CONFIG_TOOLS_BINARY_DIR@")
 set(LLVM_TOOLS_INSTALL_DIR "@LLVM_TOOLS_INSTALL_DIR@")
 set(LLVM_HAVE_OPT_VIEWER_MODULES @LLVM_HAVE_OPT_VIEWER_MODULES@)
+set(LLVM_CONFIGURATION_TYPES @CMAKE_CONFIGURATION_TYPES@)
 
 if(NOT TARGET LLVMSupport)
   set(LLVM_EXPORTED_TARGETS "@LLVM_CONFIG_EXPORTS@")
   include("@LLVM_CONFIG_EXPORTS_FILE@")
   @llvm_config_include_buildtree_only_exports@
 endif()
 
 # By creating intrinsics_gen here, subprojects that depend on LLVM's
 # tablegen-generated headers can always depend on this target whether building
 # in-tree with LLVM or not.
 if(NOT TARGET intrinsics_gen)
   add_custom_target(intrinsics_gen)
 endif()
 
 set_property(GLOBAL PROPERTY LLVM_TARGETS_CONFIGURED On)
 include(${LLVM_CMAKE_DIR}/LLVM-Config.cmake)