imageworks/OpenColorIO — pull request #377 by pinotree (2014-09-12 21:54:45+00:00)
Title: Fix define check for GCC symbol visibility

Define the ``__attribute__`` symbol visibility (for GCC) by checking for GCC itself, instead of different OSes (which might also have different compilers).

Clang should define ``__GNUC__`` as well for GCC compatibility, so this should cause no regressions (while fixing the symbols visibility on any OS which uses GCC).