From: Wolfgang Bangerth <bangerth@colostate.edu>
Date: Mon, 2 Mar 2020 03:48:51 +0000 (-0700)
Subject: Add a changelog entry.
X-Git-Tag: v9.2.0-rc1~481^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=44d9e83e858052877bd258a0f352367699fbcebc;p=dealii.git

Add a changelog entry.
---

diff --git a/doc/news/changes/incompatibilities/20200301Bangerth b/doc/news/changes/incompatibilities/20200301Bangerth
new file mode 100644
index 0000000000..f43fb36bd9
--- /dev/null
+++ b/doc/news/changes/incompatibilities/20200301Bangerth
@@ -0,0 +1,14 @@
+New: The underlying type for types::global_dof_index used to be
+`unsigned long long int`. On all reasonable systems, this is actually
+a 64-bit unsigned integer type, but the name wouldn't tell you that
+unless you already knew. This is now fixed: Instead of the mouthful
+of a type, we now use the more concise `uint64_t`: An unsigned integer
+type with exactly 64 bits of accuracy.
+<br>
+Strictly speaking, this may be an incompatible change: On some
+systems, `unsigned long long int` and `uint64_t` may have the same
+size, but are not the same type. In practice, as long as you have used
+the type `types::global_dof_index`, you will not see any difference at
+all.
+<br>
+(Wolfgang Bangerth, 2020/03/01)