add changes entry

diff --git a/doc/news/changes/incompatibilities/20180101MatthiasMaier b/doc/news/changes/incompatibilities/20180101MatthiasMaier
new file mode 100644 (file)
index 0000000..0ffaae8
--- /dev/null
+++ b/doc/news/changes/incompatibilities/20180101MatthiasMaier
@@ -0,0 +1,7 @@
+Changed: It is now necessary to explicitly enable MPI support when
+configuring deal.II via -DDEAL_II_WITH_MPI=ON, or -DWITH_MPI=ON on the
+command line. The old behavior of just specifying an MPI compiler wrapper
+via environemnt, or CMAKE_(C|CXX)_COMPILER does not work any more.
+<br>
+(Matthias Maier, 2018/01/01)
+