From ae1cc995e358ef3635bf1f3c3f4f5c0f15c40f98 Mon Sep 17 00:00:00 2001
From: Jonas Devlieghere <jonas@devlieghere.com>
Date: Fri, 29 Mar 2019 17:35:42 +0000
Subject: [PATCH] [Cmake] Unify python variables

FindPythonInterp and FindPythonLibs do two things, they set some
variables (PYTHON_LIBRARIES, PYTHON_INCLUDE_DIRS) and update the cached
variables (PYTHON_LIBRARY, PYTHON_INCLUDE_DIR) which are also used to
specify a custom python installation.

I believe the canonical way to do this is to use the PYTHON_LIBRARIES
and PYTHON_INCLUDE_DIRS variables instead of the cached ones. However,
since the cached variables are accessible from the cache and GUI, this
is a lot less confusing when you're trying to debug why a variable did
or didn't get the value you expected. Furthermore, as far as I can tell,
the implementation uses the cached variables to set their LIBRARIES/DIRS
counterparts. This is also the reason this works today even though we
mix-and-match.

Differential revision: https://reviews.llvm.org/D59968

llvm-svn: 357282
---
 lldb/cmake/modules/LLDBConfig.cmake | 24 +++++++++++++-----------
 lldb/scripts/CMakeLists.txt         |  2 --
 lldb/source/Utility/CMakeLists.txt  |  2 +-
 3 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/lldb/cmake/modules/LLDBConfig.cmake b/lldb/cmake/modules/LLDBConfig.cmake
index 20b4aa8..b8b047b 100644
--- a/lldb/cmake/modules/LLDBConfig.cmake
+++ b/lldb/cmake/modules/LLDBConfig.cmake
@@ -135,10 +135,10 @@ function(find_python_libs_windows)
     return()
   endif()
 
-  file(TO_CMAKE_PATH "${PYTHON_HOME}/Include" PYTHON_INCLUDE_DIRS)
+  file(TO_CMAKE_PATH "${PYTHON_HOME}/Include" PYTHON_INCLUDE_DIR)
 
-  if(EXISTS "${PYTHON_INCLUDE_DIRS}/patchlevel.h")
-    file(STRINGS "${PYTHON_INCLUDE_DIRS}/patchlevel.h" python_version_str
+  if(EXISTS "${PYTHON_INCLUDE_DIR}/patchlevel.h")
+    file(STRINGS "${PYTHON_INCLUDE_DIR}/patchlevel.h" python_version_str
          REGEX "^#define[ \t]+PY_VERSION[ \t]+\"[^\"]+\"")
     string(REGEX REPLACE "^#define[ \t]+PY_VERSION[ \t]+\"([^\"+]+)[+]?\".*" "\\1"
          PYTHONLIBS_VERSION_STRING "${python_version_str}")
@@ -146,7 +146,7 @@ function(find_python_libs_windows)
     string(REGEX REPLACE "([0-9]+)[.]([0-9]+)[.][0-9]+" "python\\1\\2" PYTHONLIBS_BASE_NAME "${PYTHONLIBS_VERSION_STRING}")
     unset(python_version_str)
   else()
-    message("Unable to find ${PYTHON_INCLUDE_DIRS}/patchlevel.h, Python installation is corrupt.")
+    message("Unable to find ${PYTHON_INCLUDE_DIR}/patchlevel.h, Python installation is corrupt.")
     message("Python support will be disabled for this build.")
     set(LLDB_DISABLE_PYTHON 1 PARENT_SCOPE)
     return()
@@ -225,12 +225,12 @@ function(find_python_libs_windows)
   set (PYTHON_EXECUTABLE ${PYTHON_EXECUTABLE} PARENT_SCOPE)
   set (PYTHON_LIBRARY ${PYTHON_LIBRARY} PARENT_SCOPE)
   set (PYTHON_DLL ${PYTHON_DLL} PARENT_SCOPE)
-  set (PYTHON_INCLUDE_DIRS ${PYTHON_INCLUDE_DIRS} PARENT_SCOPE)
+  set (PYTHON_INCLUDE_DIR ${PYTHON_INCLUDE_DIR} PARENT_SCOPE)
 
   message("-- LLDB Found PythonExecutable: ${PYTHON_RELEASE_EXE} and ${PYTHON_DEBUG_EXE}")
   message("-- LLDB Found PythonLibs: ${PYTHON_RELEASE_LIB} and ${PYTHON_DEBUG_LIB}")
   message("-- LLDB Found PythonDLL: ${PYTHON_RELEASE_DLL} and ${PYTHON_DEBUG_DLL}")
-  message("-- LLDB Found PythonIncludeDirs: ${PYTHON_INCLUDE_DIRS}")
+  message("-- LLDB Found PythonIncludeDirs: ${PYTHON_INCLUDE_DIR}")
 endfunction(find_python_libs_windows)
 
 if (NOT LLDB_DISABLE_PYTHON)
@@ -243,17 +243,19 @@ if (NOT LLDB_DISABLE_PYTHON)
       add_definitions( -DLLDB_PYTHON_HOME="${LLDB_PYTHON_HOME}" )
     endif()
   else()
-    find_package(PythonLibs REQUIRED)
+    find_package(PythonInterp)
+    find_package(PythonLibs)
   endif()
-  
-  if (PYTHON_INCLUDE_DIRS)
-    include_directories(${PYTHON_INCLUDE_DIRS})
+
+  if (PYTHON_INCLUDE_DIR)
+    include_directories(${PYTHON_INCLUDE_DIR})
   endif()
 endif()
 
 if (LLDB_DISABLE_PYTHON)
-  unset(PYTHON_INCLUDE_DIRS)
+  unset(PYTHON_INCLUDE_DIR)
   unset(PYTHON_LIBRARY)
+  unset(PYTHON_EXECUTABLE)
   add_definitions( -DLLDB_DISABLE_PYTHON )
 endif()
 
diff --git a/lldb/scripts/CMakeLists.txt b/lldb/scripts/CMakeLists.txt
index 7dec75b..b394be3 100644
--- a/lldb/scripts/CMakeLists.txt
+++ b/lldb/scripts/CMakeLists.txt
@@ -9,8 +9,6 @@ set(SWIG_HEADERS
   ${LLDB_SOURCE_DIR}/include/lldb/lldb-versioning.h
 )
 
-include(FindPythonInterp)
-
 if(LLDB_BUILD_FRAMEWORK)
   set(framework_arg --framework --target-platform Darwin)
 endif()
diff --git a/lldb/source/Utility/CMakeLists.txt b/lldb/source/Utility/CMakeLists.txt
index 254fb41..280ed3c 100644
--- a/lldb/source/Utility/CMakeLists.txt
+++ b/lldb/source/Utility/CMakeLists.txt
@@ -27,7 +27,7 @@ if(Backtrace_FOUND)
 endif()
 
 if (NOT LLDB_DISABLE_PYTHON AND NOT LLVM_BUILD_STATIC)
-  list(APPEND LLDB_SYSTEM_LIBS ${PYTHON_LIBRARIES})
+  list(APPEND LLDB_SYSTEM_LIBS ${PYTHON_LIBRARY})
 endif()
 
 list(APPEND LLDB_SYSTEM_LIBS ${system_libs})
-- 
2.7.4