python · sumanthratna · Jul 1, 2020 · Jul 1, 2020 · Jul 1, 2020
diff --git a/Lib/ctypes/util.py b/Lib/ctypes/util.py
@@ -70,15 +70,25 @@ def find_library(name):
 elif os.name == "posix" and sys.platform == "darwin":
    from ctypes.macholib.dyld import dyld_find as _dyld_find
    def find_library(name):
-        possible = ['lib%s.dylib' % name,
-                    '%s.dylib' % name,
-                    '%s.framework/%s' % (name, name)]
-        for name in possible:
-            try:
-                return _dyld_find(name)
-            except ValueError:
-                continue
-        return None
+        from platform import mac_ver
+        macos_version = mac_ver()[0]
+        if macos_version == '10.16' or macos_version == '11.0':
+            # see https://bugs.python.org/issue41179
+            # macOS Big Sur no longer copies dynamic libraries
+            # TODO (@sumanthratna): we shouldn't change this logic
+            # https://github.com/python/cpython/blob/0a2ee77547c0e25f081cfb6507a1ab8fecbd683a/Lib/ctypes/macholib/dyld.py#L15-L29
+            # this probably requires a change to ctypes.macholib.dyld.dyld_find
+            pass
+        else:
+            possible = ['lib%s.dylib' % name,
+                        '%s.dylib' % name,
+                        '%s.framework/%s' % (name, name)]
+            for name in possible:
+                try:
+                    return _dyld_find(name)
+                except ValueError:
+                    continue
+            return None

 elif sys.platform.startswith("aix"):
    # AIX has two styles of storing shared libraries