compiler.tree.modular-arithmetic: Don't require that fixnum+ works on tuple slots marked fixnum. This is probably a speed regression. XXX revisit

basis/compiler/tree/modular-arithmetic/modular-arithmetic-tests.factor

@@ -21,10 +21,12 @@ IN: compiler.tree.modular-arithmetic.tests
 
 TUPLE: declared-fixnum { x fixnum } ;
 
-[ t ] [
-    [ { declared-fixnum } declare [ 1 + ] change-x ]
-    { + fixnum+ >fixnum } inlined?
-] unit-test
+! XXX: As of .97, we do a bounds check and throw an error on overflow, so we can't
+! use fixnum+ here. If this is too big a regression, we can revert it.
+! [ t ] [
+    ! [ { declared-fixnum } declare [ 1 + ] change-x ]
+    ! { + fixnum+ >fixnum } inlined?
+! ] unit-test
 
 [ t ] [
     [ { declared-fixnum } declare x>> drop ]