2014b uses HG2 in opposite to 2010b's HG1. If the code assumes, that graphic handles are double values, it will fail. uitree has a different calling style and the resize behavior of figures have changed during they are opened. dataread was removed in 2016b already, and the change of strncmp(a,b,0) happend before 2016b also.
There are many pitfalls between Matlab versions. Most of them are tiny, but can affect your work. I did some tests for compatibility on larger codes (some 100'000 lines of code). Here only exhaustive unit-tests could reveal the problems: Each subfunction is called with a representative set of allowed inputs and teh results are compared with the expectations. In addition some invalid inputs are provided and the regular reaction is checked. Afterwards some integration tests checked the output of the whole program suite.
Writing unit-tests for each and every tiny or dumb function seems to be very tedious. Without such tests a migrating large codes cannot be performed reliably.
