Add libdl on Linux systems.

QuLogic · QuLogic · commit 972cfc6dbcfe · 2018-01-25T15:57:46.000-05:00
Not linking with libdl causes errors when -z defs is in the linker
flags.
diff --git a/setupext.py b/setupext.py
@@ -1493,6 +1493,8 @@ def add_flags(self, ext):
         if sys.platform == 'win32':
             # PSAPI library needed for finding Tcl / Tk at run time
             ext.libraries.extend(['psapi'])
+        elif sys.platform.startswith('linux'):
+            ext.libraries.extend(['dl'])
 
 
 class BackendGtk(OptionalBackendPackage):
