Resubmit "Fix llvm-lit script generation in libcxx."

After speaking with the libcxx owners, they agreed that this is
a bug in the bot that needs to be fixed by the bot owners, and
the CMake changes are correct.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@313643 91177308-0d34-0410-b5e6-96231b3b80d8

CMakeLists.txt

@@ -653,6 +653,7 @@ endif()
 #
 # However, since some submission systems strip test/ subdirectories, check for
 # it before adding it.
+
 if(IS_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/test")
   add_subdirectory(test)
 endif()
@@ -660,6 +661,15 @@ if (LIBCXX_INCLUDE_TESTS)
   add_subdirectory(lib/abi)
 endif()
 
+if (LIBCXX_STANDALONE_BUILD AND EXISTS "${LLVM_MAIN_SRC_DIR}/utils/llvm-lit")
+  # Make sure the llvm-lit script is generated into the bin directory, and do
+  # it after adding all tests, since the generated script will only work
+  # correctly discovered tests against test locations from the source tree that
+  # have already been discovered.
+  add_subdirectory(${LLVM_MAIN_SRC_DIR}/utils/llvm-lit
+                   ${CMAKE_CURRENT_BINARY_DIR}/llvm-lit)
+endif()
+
 if (LIBCXX_INCLUDE_DOCS)
   add_subdirectory(docs)
 endif()

cmake/Modules/HandleOutOfTreeLLVM.cmake

@@ -106,6 +106,11 @@ macro(configure_out_of_tree_llvm)
     set(LLVM_ENABLE_SPHINX OFF)
   endif()
 
+  # In a standalone build, we don't have llvm to automatically generate the
+  # llvm-lit script for us.  So we need to provide an explicit directory that
+  # the configurator should write the script into.
+  set(LLVM_LIT_OUTPUT_DIR "${libcxx_BINARY_DIR}/bin")
+
   # Required LIT Configuration ------------------------------------------------
   # Define the default arguments to use with 'lit', and an option for the user
   # to override.

test/CMakeLists.txt

@@ -49,10 +49,9 @@ set(LIBCXX_EXECUTOR "None" CACHE STRING
 
 set(AUTO_GEN_COMMENT "## Autogenerated by libcxx configuration.\n# Do not edit!")
 
-configure_file(
+configure_lit_site_cfg(
   ${CMAKE_CURRENT_SOURCE_DIR}/lit.site.cfg.in
-  ${CMAKE_CURRENT_BINARY_DIR}/lit.site.cfg
-  @ONLY)
+  ${CMAKE_CURRENT_BINARY_DIR}/lit.site.cfg)
 
 set(LIBCXX_TEST_DEPS "")