/in/foo.c:22:9: warning: bad option '-fwhole-program' to pragma 'optimize' [-Wpragmas]
   22 | #pragma GCC optimize("-fwhole-program")
      |         ^~~
/in/foo.c:29:9: warning: bad option '-fstrict-overflow' to pragma 'optimize' [-Wpragmas]
   29 | #pragma GCC optimize("-fstrict-overflow")
      |         ^~~
/in/foo.c:31:9: warning: bad option '-fcse-skip-blocks' to pragma 'optimize' [-Wpragmas]
   31 | #pragma GCC optimize("-fcse-skip-blocks")
      |         ^~~
/in/foo.c:45:9: warning: bad option '-funsafe-loop-optimizations' to pragma 'optimize' [-Wpragmas]
   45 | #pragma GCC optimize("-funsafe-loop-optimizations")
      |         ^~~
/in/foo.c:50:10: fatal error: iostream: No such file or directory
   50 | #include <iostream>
      |          ^~~~~~~~~~
compilation terminated.