* std.fs.File.copyRange and copyRangeAll return u64 instead of usize -
the returned value is how much of the `len` is transferred, so the
types should match. This removes the need for an `@intCast`.
* fix typo that removed a subtraction
* Fix the size of codegen.AnyMCValue which gave me a compile error when
I tried to build self-hosted for i386-linux.
* restore the coercion to u64 of syms_sect.sh_info. We want to make
sure the multiplication happens with 64 bits and not the smaller type
used by the ELF format.
* fix another offset parameter in link/Elf.zig to be u64 instead of usize
* add a nice little TODO note to help out Jakub
* FmtError already has FileTooBig in it; we just need to return it.
b2b0bf0506