diff --git a/Include/pymacro.h b/Include/pymacro.h
index 73521be00fcd1ad..f08ed1a1ecf0f9f 100644
--- a/Include/pymacro.h
+++ b/Include/pymacro.h
@@ -25,7 +25,7 @@
 // behaviour. So only define if building as C, not C++ (if __cplusplus is
 // not defined), and only for C11-17.
 #if !defined(static_assert) && (defined(__GNUC__) || defined(__clang__)) \
-     && !defined(_Py_STDC_VERSION) \
+     && defined(_Py_STDC_VERSION) \
      && _Py_STDC_VERSION >= 201112L && _Py_STDC_VERSION <= 201710L
 #  define static_assert _Static_assert
 #endif
diff --git a/Misc/NEWS.d/next/Build/2026-10-26-21-00-00.gh-issue-160704.ZRYLKF.rst b/Misc/NEWS.d/next/Build/2026-10-26-21-00-00.gh-issue-160704.ZRYLKF.rst
new file mode 100644
index 000000000000000..330415c155cd89a
--- /dev/null
+++ b/Misc/NEWS.d/next/Build/2026-10-26-21-00-00.gh-issue-160704.ZRYLKF.rst
@@ -0,0 +1,2 @@
+Fix C11-C17 builds with old C library headers that do not define
+``static_assert``, including glibc versions older than 2.16.