Replace abort with Py_FatalError.
diff --git a/Modules/regexpr.c b/Modules/regexpr.c
index 8fe1321..e6a5417 100644
--- a/Modules/regexpr.c
+++ b/Modules/regexpr.c
@@ -1243,7 +1243,7 @@
 		}
 		case Rquote:
 		{
-			abort();
+			Py_FatalError("Rquote");
 			/*NOTREACHED*/
 		}
 		case Rbol: