From 4f1b0822a51395be5c22e7a8bdecada81397e823 Mon Sep 17 00:00:00 2001 From: Nehal J Wani Date: Sat, 5 Apr 2025 16:12:47 +0100 Subject: [PATCH 2/2] Ensure c-extension looks up symbols locally From man(3) dlopen: RTLD_DEEPBIND (since glibc 2.3.4) Place the lookup scope of the symbols in this shared object ahead of the global scope. This means that a self-contained object will use its own symbols in preference to global symbols with the same name contained in objects that have already been loaded. --- zstandard/__init__.py | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/zstandard/__init__.py b/zstandard/__init__.py index 9c32d9d..ccc53fc 100644 --- a/zstandard/__init__.py +++ b/zstandard/__init__.py @@ -17,6 +17,7 @@ from __future__ import absolute_import, unicode_literals import builtins import io import os +import sys import platform from typing import ByteString @@ -36,7 +37,10 @@ _module_policy = os.environ.get("PYTHON_ZSTANDARD_IMPORT_POLICY", "default") if _module_policy == "default": if platform.python_implementation() in ("CPython",): + dlopen_flags_prev = sys.getdlopenflags() + sys.setdlopenflags(os.RTLD_NOW | os.RTLD_DEEPBIND) from .backend_c import * # type: ignore + sys.setdlopenflags(dlopen_flags_prev) backend = "cext" elif platform.python_implementation() in ("PyPy",): -- 2.49.0