Compile options for Windows+gcc are terrible! Why?!?!
The compile options for release builds with gcc on Windows are "-g -O2" (check line 88 of the file ".../build/windows.gcc.inc"). Why no link-time optimization, why not turn on all optimizations? And even more important: why add debug information for release builds?!?!
I would propose the options "-O3 -flto". Of course everyone can patch his file before compiling with gcc on Windows.