Merging r352374:

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r352374 | mgorny | 2019-01-28 16:16:03 +0100 (Mon, 28 Jan 2019) | 18 lines

[cmake] Fix get_llvm_lit_path() to respect LLVM_EXTERNAL_LIT always

Refactor the get_llvm_lit_path() logic to respect LLVM_EXTERNAL_LIT,
and require the fallback to be defined explicitly
as LLVM_DEFAULT_EXTERNAL_LIT. This fixes building libcxx standalone
after r346888.

The old logic was using LLVM_EXTERNAL_LIT both as user-defined cache
variable and an optional pre-definition of default value from caller
(e.g. libcxx). It included a hack to make this work by assigning
the value back and forth but it was fragile and stopped working
in libcxx.

The new logic is simpler and more transparent. Default value is
provided in a separate variable, and used only when user-specified
variable is empty (i.e. not overriden).

Differential Revision: https://reviews.llvm.org/D57282
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llvm-svn: 352496

1 files changed, 1 insertions, 1 deletions

diff --git a/lldb/cmake/modules/LLDBStandalone.cmake b/lldb/cmake/modules/LLDBStandalone.cmake
index e63b269..a9059dd 100644
--- a/lldb/cmake/modules/LLDBStandalone.cmake
+++ b/lldb/cmake/modules/LLDBStandalone.cmake
@@ -58,7 +58,7 @@ if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
   set(LLVM_DIR ${LLVM_OBJ_ROOT}/cmake/modules/CMakeFiles CACHE PATH "Path to LLVM build tree CMake files")
   set(LLVM_BINARY_DIR ${LLVM_OBJ_ROOT} CACHE PATH "Path to LLVM build tree")
   set(LLVM_MAIN_SRC_DIR ${MAIN_SRC_DIR} CACHE PATH "Path to LLVM source tree")
-  set(LLVM_EXTERNAL_LIT ${LLVM_TOOLS_BINARY_DIR}/llvm-lit CACHE PATH "Path to llvm-lit")
+  set(LLVM_DEFAULT_EXTERNAL_LIT ${LLVM_TOOLS_BINARY_DIR}/llvm-lit CACHE PATH "Path to llvm-lit")
 
   find_program(LLVM_TABLEGEN_EXE "llvm-tblgen" ${LLVM_TOOLS_BINARY_DIR}
     NO_DEFAULT_PATH)