http://bugs.winehq.org/show_bug.cgi?id=33125
--- Comment #101 from Andrey Gusev andrey.goosev@gmail.com ---
From changes list for gcc 4.8.2
"A new general optimization level, -Og, has been introduced. It addresses the need for fast compilation and a superior debugging experience while providing a reasonable level of runtime performance. Overall experience for development should be better than the default optimization level -O0."
Upstream?