[lldb][windows] add a warning if CMake's version is inferior to 3.30

[charles-zablit]

#140443 makes use of the CMake variable Python3_EXECUTABLE_DEBUG, which was introduced in CMake version 3.30. On systems with an inferior version of cmake, the lit tests will try to run with an empty config.python_executable.

This PR adds a warning and falls back to using Python3_EXECUTABLE if the CMake version is less than 3.30.

[llvmbot]

@llvm/pr-subscribers-lldb

Author: Charles Zablit (charles-zablit)

Changes

#140443 makes use of the CMake variable Python3_EXECUTABLE_DEBUG, which was introduced in CMake version 3.30. On systems with an inferior version of cmake, the lit tests will try to run with an empty config.python_executable.

This PR adds a warning and falls back to using Python3_EXECUTABLE if the CMake version is less than 3.30.

---

Full diff: https://github.com/llvm/llvm-project/pull/164346.diff

1 Files Affected:

• (modified) lldb/test/API/CMakeLists.txt (+6-1)

diff --git a/lldb/test/API/CMakeLists.txt b/lldb/test/API/CMakeLists.txt
index b1ace6296f46a..e3bffbc73c394 100644
--- a/lldb/test/API/CMakeLists.txt
+++ b/lldb/test/API/CMakeLists.txt
@@ -140,7 +140,12 @@ if(CMAKE_HOST_APPLE)
 endif()
 
 if(WIN32 AND CMAKE_BUILD_TYPE STREQUAL Debug)
-  set(LLDB_PYTHON_API_TEST_EXECUTABLE "${Python3_EXECUTABLE_DEBUG}")
+  if(${CMAKE_VERSION} VERSION_LESS "3.30")
+    message(WARNING "CMake version is inferior to 3.30. Some lldb tests will fail.")
+    set(LLDB_PYTHON_API_TEST_EXECUTABLE "${Python3_EXECUTABLE}")
+  else()
+    set(LLDB_PYTHON_API_TEST_EXECUTABLE "${Python3_EXECUTABLE_DEBUG}")
+  endif()
 else()
   set(LLDB_PYTHON_API_TEST_EXECUTABLE "${Python3_EXECUTABLE}")
 endif()

[Nerixyz]

Change LGTM.

I just noticed that my change from #140443 is incompatible with multi-config generators, but I don't know CMake that well to fix this (nor did I ever use a multi-config generator intentionally). There seems to be the Python3::InterpreterMultiConfig target in 3.30.