Clarify fix for 1989/paul

I have clarified that the reason I fixed the segfault in macOS is
because without it the entry did not work.

thanks-for-fixes.md

@@ -496,9 +496,9 @@ author's remarks. See the README.md for details.
 
 ## [1989/paul](1989/paul/paul.c) ([README.md](1989/paul/README.md]))
 
-Cody fixed a segfault under macOS. The problem was that the int (from `#define
-f`) should be a long. This became apparent when he was using lldb and saw that
-the type of a pointer was too `long` :-)
+Cody fixed a segfault under macOS that prevented it from working. The problem
+was that the int (from `#define f`) should be a long. This became apparent when
+he was using lldb and saw that the type of a pointer was too `long` :-)
 
 
 ## [1989/robison](1989/robison/robison.c) ([README.md](1989/robison/README.md]))