Improve libpython detection (#394)

See #392.

commands/python.py

@@ -1,8 +1,8 @@
-from distutils import sysconfig
 from commands.util import is_osx
 from commands.util import is_windows
 from commands.util import is_bsd
 import os
+import sysconfig
 
 
 def get_python_libs():
@@ -37,16 +37,36 @@ def get_python_lib_dir():
 def get_libpython():
  """
  Searches for the Python library, e.g. libpython<version>.so.
- Primarily used for setting up LD_PRELOAD.
+ Used by setup.py to set PYTHON_LDLIBRARY, and by scripts to set up LD_PRELOAD.
  """
- lib_python = os.path.join(sysconfig.get_config_var('LIBDIR'),
- sysconfig.get_config_var('LDLIBRARY'))
+ libdir = sysconfig.get_config_var('LIBDIR')
+ ldlibrary = sysconfig.get_config_var('LDLIBRARY')
+ if libdir is None or ldlibrary is None:
+ return None
+
+ lib_python = os.path.join(libdir, ldlibrary)
  if os.path.exists(lib_python):
  return lib_python
- else:
- # x64 systems will tend to also have a MULTIARCH folder
- lib_python = os.path.join(sysconfig.get_config_var('LIBDIR'),
- sysconfig.get_config_var('MULTIARCH'),
- sysconfig.get_config_var('LDLIBRARY'))
+
+ # x64 systems will tend to also have a MULTIARCH folder
+ multiarch = sysconfig.get_config_var('MULTIARCH')
+ if multiarch is not None:
+ lib_python = os.path.join(libdir, multiarch, ldlibrary)
+ if os.path.exists(lib_python):
+ return lib_python
+
+ # HACK: Non-existent static library is a known issue with conda-forge python;
+ # see: https://github.com/conda-forge/python-feedstock/issues/565
+ # Let's also look for a shared library in this case.
+ if ldlibrary.endswith('.a'):
+ ldshared = ldlibrary[:-1] + 'so'
+ lib_python = os.path.join(libdir, ldshared)
  if os.path.exists(lib_python):
  return lib_python
+ if multiarch is not None:
+ lib_python = os.path.join(libdir, multiarch, ldshared)
+ if os.path.exists(lib_python):
+ return lib_python
+
+ # give up
+ return None

setup.py

@@ -20,7 +20,7 @@
 from commands.java import build_java, get_java_home, get_java_include,\
  get_java_linker_args, build_jar, get_java_lib_folders, get_java_libraries, setup_java
 from commands.javadoc import javadoc
-from commands.python import get_python_libs, get_python_linker_args
+from commands.python import get_libpython, get_python_libs, get_python_linker_args
 from commands.scripts import build_scripts
 from commands.test import test
 from commands.util import is_windows
@@ -65,7 +65,13 @@ def read_file(name):
  ('JEP_NUMPY_ENABLED', numpy_found),
  ('VERSION', '"{0}"'.format(VERSION)),
  ]
- ldlib = sysconfig.get_config_var('LDLIBRARY')
+ ldlib = get_libpython()
+ if ldlib:
+ # a libpython was found, so use the basename of the discovered path
+ ldlib = os.path.basename(ldlib)
+ else:
+ # no libpython was found, so use LDLIBRARY blindly
+ ldlib = sysconfig.get_config_var('LDLIBRARY')
  if ldlib:
  defines.append(('PYTHON_LDLIBRARY', '"' + ldlib + '"'))
  if is_windows():