gh-119696: Support copied virtual environments in relocatable builds

Doc/using/configure.rst

@@ -1090,6 +1090,10 @@ Linker options
    a different directory name for the standard library, but not a nested path.
    On Linux, these paths use ``DT_RPATH``.
 
+   Copied virtual environments from non-framework shared builds require
+   directory symlinks to the base installation's libraries. Virtual environments
+   depend on their base installation and must be recreated if it moves.
+
    Dependencies stored in other directories, such as ``lib/tcltk``, may
    need additional loader search paths.
 

Lib/test/test_venv.py

@@ -1136,6 +1136,9 @@ def test_zippath_from_non_installed_posix(self):
         # LD_LIBRARY_PATH so the non-installed python can find and link
         # libpython.so
         ld_library_path = sysconfig.get_config_var("LIBDIR")
+        if (sysconfig.get_config_var("RELOCATABLE") == "yes"
+                and not sysconfig.get_config_var("PYTHONFRAMEWORK")):
+            ld_library_path = os.path.join(sys.base_exec_prefix, "lib")
         if not ld_library_path or sysconfig.is_python_build():
             ld_library_path = os.path.abspath(os.path.dirname(sys.executable))
         if sys.platform == 'darwin':
@@ -1154,7 +1157,11 @@ def test_zippath_from_non_installed_posix(self):
         # correct zip path in pythonpath.
         target_python = os.path.join(self.env_dir, self.bindir, python_exe)
         cmd = [target_python, '-S', '-c', 'import sys; print(sys.path)']
-        out, err = check_output(cmd)
+        # This interpreter also depends on libraries outside the incomplete
+        # installation used by this test.
+        with EnvironmentVarGuard() as env:
+            env[ld_library_path_env] = ld_library_path
+            out, err = check_output(cmd)
         self.assertTrue(zip_landmark.encode() in out)
 
     @requireVenvCreate

Lib/venv/__init__.py

@@ -310,6 +310,20 @@ def setup_python(self, context):
             copier(context.executable, path)
             if not os.path.islink(path):
                 os.chmod(path, 0o755)
+                if (sysconfig.get_config_var('RELOCATABLE') == 'yes'
+                        and sysconfig.get_config_var('Py_ENABLE_SHARED')
+                        and not sysconfig.get_config_var('PYTHONFRAMEWORK')):
+                    # The copied executable searches relative to this environment.
+                    # Link the base library directory so it can find libpython.
+                    if sysconfig.is_python_build():
+                        library_dir = context.python_dir
+                    else:
+                        library_dir = os.path.join(sys.base_exec_prefix, 'lib')
+                    library_link = os.path.join(
+                        context.env_dir, 'lib', 'python-base')
+                    if os.path.islink(library_link):
+                        os.unlink(library_link)
+                    os.symlink(library_dir, library_link, target_is_directory=True)
             for suffix in ('python', 'python3',
                            f'python3.{sys.version_info[1]}'):
                 path = os.path.join(binpath, suffix)

Misc/NEWS.d/next/Library/2026-10-21-20-23-00.gh-issue-119696.v3NvCp.rst

@@ -0,0 +1,4 @@
+Support copied virtual environments from non-framework shared builds configured
+with :option:`--enable-relocatable` by linking the base library directory into
+the environment. Copied environments require filesystem support for directory
+symlinks.

configure.ac

@@ -6901,7 +6901,7 @@ AS_IF([test "$enable_relocatable" = yes && test -z "$enable_framework"], [
     [Linux], [
       # Keep the dollar sign through configure, make, and the shell.
       # DT_RPATH entries can also resolve indirect dependencies.
-      RELOCATABLE_PYTHON_LDFLAGS="-Wl,--disable-new-dtags,-rpath,'\$\$ORIGIN/../lib'"
+      RELOCATABLE_PYTHON_LDFLAGS="-Wl,--disable-new-dtags,-rpath,'\$\$ORIGIN/../lib:\$\$ORIGIN/../lib/python-base'"
       RELOCATABLE_LIBPYTHON_LDFLAGS="-Wl,--disable-new-dtags,-rpath,'\$\$ORIGIN'"
       RELOCATABLE_EXTENSION_LDFLAGS="-Wl,--disable-new-dtags,-rpath,'\$\$ORIGIN/../../../lib'"
       save_LDFLAGS=$LDFLAGS
@@ -6912,7 +6912,7 @@ AS_IF([test "$enable_relocatable" = yes && test -z "$enable_framework"], [
     ],
     [Darwin], [
       RELOCATABLE_LIBPYTHON_INSTALL_NAME='@rpath/libpython$(LDVERSION).dylib'
-      RELOCATABLE_PYTHON_LDFLAGS='-Wl,-rpath,@executable_path/../lib'
+      RELOCATABLE_PYTHON_LDFLAGS='-Wl,-rpath,@executable_path/../lib -Wl,-rpath,@executable_path/../lib/python-base'
       RELOCATABLE_LIBPYTHON_LDFLAGS='-Wl,-rpath,@loader_path'
       RELOCATABLE_EXTENSION_LDFLAGS='-Wl,-rpath,@loader_path/../../../lib'
     ])