Fw: Possible missed optimization opportunity with const?
Thu Sep 1 07:19:00 GMT 2016
> It seems "extern const int foo;" with "-Wl --defsym,foo=0x1234" almost works, except GCC then uses a
> RIP-relative reference on amd64 and that can cause a relocation overflow.
> I also tried wrapping the read in an __attribute__((const))
> function, which means the return value does not depend on
> global memory:
> int __attribute__((const)) getfoo()
> return *(const int *) 0x1234;
> but GCC emitted two reads anyhow.
Yep. It should not be this hard to do this.
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