diff --git a/Modules/_decimal/_decimal.c b/Modules/_decimal/_decimal.c
index ff7c647c222..fb4e020f126 100644
--- a/Modules/_decimal/_decimal.c
+++ b/Modules/_decimal/_decimal.c
@@ -56,6 +56,11 @@
 
 #define BOUNDS_CHECK(x, MIN, MAX) x = (x < MIN || MAX < x) ? MAX : x
 
+#if defined(__GNUC__) && !defined(__INTEL_COMPILER)
+  #define UNUSED __attribute__((unused))
+#else
+  #define UNUSED
+#endif
 
 /* _Py_DEC_MINALLOC >= MPD_MINALLOC */
 #define _Py_DEC_MINALLOC 4
diff --git a/Modules/_decimal/libmpdec/mpdecimal.h b/Modules/_decimal/libmpdec/mpdecimal.h
index 35ce429f601..5a2439690c3 100644
--- a/Modules/_decimal/libmpdec/mpdecimal.h
+++ b/Modules/_decimal/libmpdec/mpdecimal.h
@@ -61,12 +61,6 @@ extern "C" {
   #define MPD_HIDE_SYMBOLS_END
 #endif
 
-#if defined(__GNUC__) && !defined(__INTEL_COMPILER)
-  #define UNUSED __attribute__((unused))
-#else
-  #define UNUSED
-#endif
-
 #if defined(_MSC_VER)
   #include "vccompat.h"
   #define EXTINLINE extern inline