-flto=N

[Dilyan Palauzov <dilyan.palauzov@xxxxxxxxx>]

Hello,

to my understanding -flto is passed during the generation of object 
files and GIMPLE, but not to the linker / or linker plugin/.  In 
particular, with -fno-fat-lto-objects the linker(-plugin) has to 
conclude that it has to make LTO.

The documentation about -flto in 4.9.3 says, that it shall be provided 
at link-time, but GCC can automatically deduce it, if any .o file was 
compiled with -flto.

Question:
  Has the N in -flto=N only effect, if it is explicitly provided to gcc 
at link time?

Thanks
  Dilian