Fixed 'maybe_unused' attribute

nobu · nobu · commit 1dfe75b0beb7 · 2021-07-06T01:13:54.000+09:00
```
../../../src/ext/bigdecimal/bigdecimal.c:303:5: error: 'maybe_unused' attribute cannot be applied to types
    ENTER(1);
    ^
```
diff --git a/ext/bigdecimal/bigdecimal.c b/ext/bigdecimal/bigdecimal.c
@@ -62,7 +62,11 @@ static ID id_eq;
 static ID id_half;
 
 /* MACRO's to guard objects from GC by keeping them in stack */
+#ifdef RBIMPL_ATTR_MAYBE_UNUSED
+#define ENTER(n) RBIMPL_ATTR_MAYBE_UNUSED() volatile VALUE vStack[n];int iStack=0
+#else
 #define ENTER(n) volatile VALUE RB_UNUSED_VAR(vStack[n]);int iStack=0
+#endif
 #define PUSH(x)  (vStack[iStack++] = (VALUE)(x))
 #define SAVE(p)  PUSH((p)->obj)
 #define GUARD_OBJ(p,y) ((p)=(y), SAVE(p))
