Fix pedantic compiler warnings

Allows building the library with the gcc -pedantic option, for improved
portabilty. In particular, this commit removes usage of C99/C++ style
single-line comments and dynamic struct initializers. This is a
continuation of the work done in commit 97b766a4, which removed most
of these warnings for decode only builds.

Change-Id: Id453d9c1d9f44cc0381b10c3869fabb0184d5966