bpo-32647: Link ctypes extension with libdl. (#5550)

The ctypes module used to depend on indirect linking for dlopen. The shared
extension is now explicitly linked against libdl on platforms with dl.

Signed-off-by: Christian Heimes <christian@python.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/setup.py b/setup.py
index f4f6e4f..8536c35 100644
--- a/setup.py
+++ b/setup.py
@@ -2005,6 +2005,10 @@ class PyBuildExt(build_ext):
             ext.libraries.append(ffi_lib)
             self.use_system_libffi = True
 
+        if sysconfig.get_config_var('HAVE_LIBDL'):
+            # for dlopen, see bpo-32647
+            ext.libraries.append('dl')
+
     def _decimal_ext(self):
         extra_compile_args = []
         undef_macros = []