March 22, 2013
1:55 p.m.
On Fri, 22 Mar 2013 13:41:25 +0800, ishare said:
Is it needed or must to compile fs and driver with -O2 option when compiling kernel ?
It's not strictly mandatory to use -O2 (for a while, -Os was the default). There are a few places that for correctness, you *cannot* use -O0. For instance, a few places where we use builtin_return_address() inside an inline (-O0 won't inline so builtin_return_address() ends up returning a pointer to a function when we want the function's parent). Since gdb and friends are able to deal with -O2 compiled code just fine, there's really no reason *not* to optimize the kernel.