multi-line comments or expressions appearing to be headings break block.

* top
#+begin_src php
/*
*do not prepend a space to 'do'
*/
b = 2
*3; // do not prepend a space to '3'
#+end_src

GNU Emacs 25.1.1 (x86_64-apple-darwin13.4.0, NS appkit-1265.21 Version
10.9.5 (Build 13F1911)) of 2016-09-20
Org mode version 9.0.9 (release_9.0.9-736-gf1b2a9 @
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