Do not clobber existing flags.
diff --git a/Modules/_decimal/libmpdec/mpdecimal.c b/Modules/_decimal/libmpdec/mpdecimal.c
index 5083710..3f43db4 100644
--- a/Modules/_decimal/libmpdec/mpdecimal.c
+++ b/Modules/_decimal/libmpdec/mpdecimal.c
@@ -3904,7 +3904,7 @@
     if (_mpd_cmp(&aa, &lim) <= 0) {
         _settriple(result, 0, 1, 0);
         _mpd_zeropad(result, ctx, status);
-        *status = MPD_Rounded|MPD_Inexact;
+        *status |= MPD_Rounded|MPD_Inexact;
         return 1;
     }