winegcc: Add support for -Ttext-segment linker flag to set image base of a dll. (try 2)

[Tijl Coosemans]

On 2013-03-06 12:25, Alexandre Julliard wrote:
> Alexandre Julliard <julliard at winehq.org> writes:
>> Tijl Coosemans <tijl at coosemans.org> writes:
>>> On 03-03-2013 17:44, André Hentschel wrote:
>>>> You would rather call it PLATFORM_FREEBSD
>>>
>>> Well, the flag isn't FreeBSD specific. It works on all ELF targets
>>> (including Linux which then wouldn't need prelink).
>>
>> Then it should be used by default, and you don't need to add a new
>> platform for it.
> 
> Actually, I looked into this and it isn't widely supported at all, so it
> can't be the default. Ideally it would need a run-time check to see if
> the option works.

Wouldn't a run-time check be too much of a performance hit?

Loading a library at a specific address not only depends on the
compile-time linker, but also on the run-time loader, so it's
probably best to implement -image-base only on PLATFORM_* where
the loader supports it. Since a target platform would then have
to choose to use PLATFORM_ELF explicitly I think it's reasonable
for PLATFORM_ELF to have a dependency on binutils>=2.20 (or
compatible) rather than a run-time test for -Ttext-segment
support.