Since Steem V13 (aka fork 13 today) has not been merged into the master branch you may have thought you were upgrading when you cloned the Steem git repository, unfortunately the changes have not been merged into the master branch. What you need to do is clone from a specific branch named "staging". This is what I did, I am not a git expert but it should work.
First I deleted my existing steem directory ( didn't have anything to backup, but if you do then... back it up :-) ). then...
git clone -b staging https://github.com/steemit/steem.git
git submodule update --init --recursive
cmake -DCMAKE_BUILD_TYPE=Release -DLOW_MEMORY_NODE=OFF CMakeLists.txt
make -j4
If your machine has more or less than 4 threads you want to change -j4 to -j(number of threads).
If you do not need a full node (most don't) change DLOW_MEMORY_NODE from OFF to ON.
If you only want to run a node and don't want to waste time building the wallet then use 'make -j4 steemd'.
Hope this helps some people