vec - clearer strided bounds error message

Co-authored-by: Jed Brown <jed@jedbrown.org>

Author: jeremylt

interface/ceed-vector.c

@@ -373,7 +373,7 @@ int CeedVectorSetValueStrided(CeedVector vec, CeedSize start, CeedSize stop, Cee
             "Cannot grant CeedVector array access, the access lock is already in use");
   CeedCheck(vec->num_readers == 0, CeedVectorReturnCeed(vec), CEED_ERROR_ACCESS, "Cannot grant CeedVector array access, a process has read access");
   CeedCall(CeedVectorGetLength(vec, &length));
-  CeedCheck(stop >= -1 && stop <= length, CeedVectorReturnCeed(vec), CEED_ERROR_ACCESS, "Invalid value for stop, must be in the range [-1, length]");
+  CeedCheck(stop >= -1 && stop <= length, CeedVectorReturnCeed(vec), CEED_ERROR_ACCESS, "Invalid value for stop %" CeedSize_FMT ", must be in the range [-1, length]", stop);
 
   if (vec->SetValueStrided) {
     CeedCall(vec->SetValueStrided(vec, start, stop, step, value));