diff --git a/Lib/platform.py b/Lib/platform.py
index cc2db9870d..ac4e3c538f 100755
--- a/Lib/platform.py
+++ b/Lib/platform.py
@@ -748,7 +748,7 @@ def _syscmd_uname(option, default=''):
 
     """ Interface to the system's uname command.
     """
-    if sys.platform in ('dos', 'win32', 'win16'):
+    if sys.platform in ('dos', 'win32', 'win16', 'emscripten'):
         # XXX Others too ?
         return default
     try:
@@ -771,7 +771,7 @@ def _syscmd_file(target, default=''):
         default in case the command should fail.
 
     """
-    if sys.platform in ('dos', 'win32', 'win16'):
+    if sys.platform in ('dos', 'win32', 'win16', 'emscripten'):
         # XXX Others too ?
         return default
     target = _follow_symlinks(target)
diff --git a/Lib/test/libregrtest/refleak.py b/Lib/test/libregrtest/refleak.py
index 0bd8288e27..bab3f95c7d 100644
--- a/Lib/test/libregrtest/refleak.py
+++ b/Lib/test/libregrtest/refleak.py
@@ -189,9 +189,9 @@ def clear_caches():
     import gc
 
     # Clear the warnings registry, so they can be displayed again
-    for mod in sys.modules.values():
-        if hasattr(mod, '__warningregistry__'):
-            del mod.__warningregistry__
+    # for mod in list(sys.modules.values()):
+    #     if hasattr(mod, '__warningregistry__'):
+    #         del mod.__warningregistry__
 
     # Flush standard output, so that buffered data is sent to the OS and
     # associated Python objects are reclaimed.
diff --git a/Lib/test/libregrtest/setup.py b/Lib/test/libregrtest/setup.py
index bf899a9e4d..8722549fd8 100644
--- a/Lib/test/libregrtest/setup.py
+++ b/Lib/test/libregrtest/setup.py
@@ -53,11 +53,11 @@ def setup_tests(ns):
     # (site.py absolutize them), the __file__ and __path__ will be absolute too.
     # Therefore it is necessary to absolutize manually the __file__ and __path__ of
     # the packages to prevent later imports to fail when the CWD is different.
-    for module in sys.modules.values():
-        if hasattr(module, '__path__'):
+    for module in list(sys.modules.values()):
+        if '__path__' in module.__dict__:
             for index, path in enumerate(module.__path__):
                 module.__path__[index] = os.path.abspath(path)
-        if hasattr(module, '__file__'):
+        if '__file__' in module.__dict__:
             module.__file__ = os.path.abspath(module.__file__)
 
     # MacOSX (a.k.a. Darwin) has a default stack size that is too small
diff --git a/Lib/test/support/script_helper.py b/Lib/test/support/script_helper.py
index ca5f9c20dd..97934039ee 100644
--- a/Lib/test/support/script_helper.py
+++ b/Lib/test/support/script_helper.py
@@ -11,6 +11,7 @@ import subprocess
 import py_compile
 import contextlib
 import shutil
+import unittest
 import zipfile
 
 from importlib.util import source_from_cache
@@ -37,6 +38,8 @@ def interpreter_requires_environment():
     situation.  PYTHONPATH or PYTHONUSERSITE are other common environment
     variables that might impact whether or not the interpreter can start.
     """
+    raise unittest.SkipTest('no subprocess')
+
     global __cached_interp_requires_environment
     if __cached_interp_requires_environment is None:
         # Try running an interpreter with -E to see if it works or not.
@@ -165,6 +168,8 @@ def spawn_python(*args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, **kw):
     kw is extra keyword args to pass to subprocess.Popen. Returns a Popen
     object.
     """
+    raise unittest.SkipTest("no subprocess")
+
     cmd_line = [sys.executable, '-E']
     cmd_line.extend(args)
     # Under Fedora (?), GNU readline can output junk on stderr when initialized,
diff --git a/Lib/test/test_code.py b/Lib/test/test_code.py
index 55faf4c427..b2201c09e7 100644
--- a/Lib/test/test_code.py
+++ b/Lib/test/test_code.py
@@ -104,7 +104,10 @@ consts: ('None',)
 
 import inspect
 import sys
-import threading
+try:
+    import threading
+except ImportError:
+    import dummy_threading as threading
 import unittest
 import weakref
 try: