diff --git a/libcxx/utils/libcxx/sym_check/extract.py b/libcxx/utils/libcxx/sym_check/extract.py
--- a/libcxx/utils/libcxx/sym_check/extract.py
+++ b/libcxx/utils/libcxx/sym_check/extract.py
@@ -11,10 +11,10 @@
 """
 import distutils.spawn
 import os.path
-import sys
 import re
+import subprocess
+import sys
 
-import libcxx.util
 from libcxx.sym_check import util
 
 extract_ignore_names = ['_init', '_fini']
@@ -51,9 +51,7 @@
         parsed symbols.
         """
         cmd = [self.nm_exe] + self.flags + [lib]
-        out, _, exit_code = libcxx.util.executeCommandVerbose(cmd)
-        if exit_code != 0:
-            raise RuntimeError('Failed to run %s on %s' % (self.nm_exe, lib))
+        out = subprocess.check_output(cmd).decode()
         fmt_syms = (self._extract_sym(l)
                     for l in out.splitlines() if l.strip())
         # Cast symbol to string.
@@ -139,9 +137,7 @@
         parsed symbols.
         """
         cmd = [self.tool] + self.flags + [lib]
-        out, _, exit_code = libcxx.util.executeCommandVerbose(cmd)
-        if exit_code != 0:
-            raise RuntimeError('Failed to run %s on %s' % (self.nm_exe, lib))
+        out = subprocess.check_output(cmd).decode()
         dyn_syms = self.get_dynsym_table(out)
         return self.process_syms(dyn_syms)
 
diff --git a/libcxx/utils/libcxx/sym_check/util.py b/libcxx/utils/libcxx/sym_check/util.py
--- a/libcxx/utils/libcxx/sym_check/util.py
+++ b/libcxx/utils/libcxx/sym_check/util.py
@@ -6,12 +6,12 @@
 #
 #===----------------------------------------------------------------------===##
 
+from pprint import pformat
 import ast
 import distutils.spawn
-import sys
 import re
-import libcxx.util
-from pprint import pformat
+import subprocess
+import sys
 
 
 def read_syms_from_list(slist):
@@ -66,11 +66,10 @@
 def demangle_symbol(symbol):
     if _cppfilt_exe is None:
         return symbol
-    out, _, exit_code = libcxx.util.executeCommandVerbose(
-        [_cppfilt_exe], input=symbol)
-    if exit_code != 0:
+    result = subprocess.run([_cppfilt_exe], input=symbol.encode(), capture_output=True)
+    if result.returncode != 0:
         return symbol
-    return out
+    return result.stdout.decode()
 
 
 def is_elf(filename):