From: Wolfgang Bangerth <bangerth@math.tamu.edu>
Date: Wed, 20 Apr 2016 02:53:02 +0000 (-0500)
Subject: Reset object to native state in IndexSet::clear().
X-Git-Tag: v8.5.0-rc1~1093^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ff8a0fb360dd7d4908e54ddec755977e8d585848;p=dealii.git

Reset object to native state in IndexSet::clear().

IndexSet stores an index into an array. Upon construction, this index is set
to an invalid value (because the array is empty), whereas after IndexSet::clear()
the index was set to zero -- a perfectly reasonable, and consequently objectionable
index. This patch sets the index to an invalid value instead, as is also
done in the constructor.
---

diff --git a/include/deal.II/base/index_set.h b/include/deal.II/base/index_set.h
index 99e191702b..1fa278b935 100644
--- a/include/deal.II/base/index_set.h
+++ b/include/deal.II/base/index_set.h
@@ -1222,9 +1222,11 @@ inline
 void
 IndexSet::clear ()
 {
+  // reset so that there are no indices in the set any more; however,
+  // as documented, the index set retains its size
   ranges.clear ();
-  largest_range = 0;
   is_compressed = true;
+  largest_range = numbers::invalid_unsigned_int;
 }