Merging r372835:

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r372835 | mgorny | 2019-09-25 02:47:35 -0700 (Wed, 25 Sep 2019) | 12 lines

[lldb] [cmake] Fix installing Python modules on systems using /usr/lib

Fix installing Python modules on systems that use /usr/lib for Python
while installing other libraries in /usr/lib64.  Rewrite CMake logic
to query correct directories from Python, similarly to how
prepare_binding_Python.py does it.  Furthermore, change the regex used
in get_relative_lib_dir.py to allow 'lib' without suffix.

I think that the code can be further improved but I'd like to take
this enterprise in smaller steps in case one of them breaks something.

Differential Revision: https://reviews.llvm.org/D67890
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Author: mgorny

lldb/scripts/CMakeLists.txt

@@ -42,15 +42,18 @@ add_custom_target(swig_wrapper ALL DEPENDS
 )
 
 if(NOT LLDB_BUILD_FRAMEWORK)
-  if(CMAKE_SYSTEM_NAME MATCHES "Windows")
-    set(swig_python_subdir site-packages)
-  else()
-    set(swig_python_subdir python${PYTHON_VERSION_MAJOR}.${PYTHON_VERSION_MINOR})
-  endif()
-
-  set(SWIG_PYTHON_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/${swig_python_subdir})
-  set(SWIG_INSTALL_DIR lib${LLVM_LIBDIR_SUFFIX})
+  execute_process(
+    COMMAND ${PYTHON_EXECUTABLE}
+        -c "import distutils.sysconfig, sys; print(distutils.sysconfig.get_python_lib(True, False, sys.argv[1]))"
+        ${CMAKE_BINARY_DIR}
+    OUTPUT_VARIABLE SWIG_PYTHON_DIR
+    OUTPUT_STRIP_TRAILING_WHITESPACE)
+  execute_process(
+    COMMAND ${PYTHON_EXECUTABLE}
+        -c "import distutils.sysconfig; print(distutils.sysconfig.get_python_lib(True, False, ''))"
+    OUTPUT_VARIABLE SWIG_INSTALL_DIR
+    OUTPUT_STRIP_TRAILING_WHITESPACE)
 
   # Install the LLDB python module
-  install(DIRECTORY ${SWIG_PYTHON_DIR} DESTINATION ${SWIG_INSTALL_DIR})
+  install(DIRECTORY ${SWIG_PYTHON_DIR}/ DESTINATION ${SWIG_INSTALL_DIR})
 endif()

lldb/scripts/get_relative_lib_dir.py

@@ -23,7 +23,7 @@ def get_python_relative_libdir():
     # right answer always.
     arch_specific_libdir = distutils.sysconfig.get_python_lib(True, False)
     split_libdir = arch_specific_libdir.split(os.sep)
-    lib_re = re.compile(r"^lib.+$")
+    lib_re = re.compile(r"^lib.*$")
 
     for i in range(len(split_libdir)):
         match = lib_re.match(split_libdir[i])