diff --git a/Lib/sysconfig.py b/Lib/sysconfig.py
index 517b13acaf6823..c747f0b4d4ad23 100644
--- a/Lib/sysconfig.py
+++ b/Lib/sysconfig.py
@@ -845,6 +845,9 @@ def expand_makefile_vars(s, vars):
     """
     import re
 
+    _findvar1_rx = r"\$\(([A-Za-z][A-Za-z0-9_]*)\)"
+    _findvar2_rx = r"\${([A-Za-z][A-Za-z0-9_]*)}"
+
     # This algorithm does multiple expansion, so if vars['foo'] contains
     # "${bar}", it will expand ${foo} to ${bar}, and then expand
     # ${bar}... and so forth.  This is fine as long as 'vars' comes from
diff --git a/Misc/NEWS.d/next/Library/2025-01-18-11-04-44.gh-issue-128978.hwg7-w.rst b/Misc/NEWS.d/next/Library/2025-01-18-11-04-44.gh-issue-128978.hwg7-w.rst
new file mode 100644
index 00000000000000..521496d6a2f8c2
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2025-01-18-11-04-44.gh-issue-128978.hwg7-w.rst
@@ -0,0 +1,2 @@
+Fix a :exc:`NameError` in :func:`!sysconfig.expand_makefile_vars`. Patch by
+Bénédikt Tran.