diff --git a/Modules/_ctypes/ctypes.h b/Modules/_ctypes/ctypes.h
index 3533cfc66fc56d..3b6d390728a07f 100644
--- a/Modules/_ctypes/ctypes.h
+++ b/Modules/_ctypes/ctypes.h
@@ -489,14 +489,14 @@ struct tagPyCArgObject {
         int i;
         long l;
         long long q;
-        long double D;
+        long double g;
         double d;
         float f;
         void *p;
 #if defined(Py_HAVE_C_COMPLEX) && defined(Py_FFI_SUPPORT_C_COMPLEX)
-        double complex C;
-        float complex E;
-        long double complex F;
+        double complex D;
+        float complex F;
+        long double complex G;
 #endif
     } value;
     PyObject *obj;