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GOLD handling of weak symbols (including x86 vs. ARM)

Ian Lance Taylor iant@google.com
Fri Nov 5 17:33:00 GMT 2010 
Richard Sandiford <richard.sandiford@linaro.org> writes:

> Well, the problem is that Thumb doesn't have separate relocs for
> non-@PLT and @PLT function calls.  (ARM itself only has it with a
> legacy relocation, R_ARM_PLT32.)

Yeah, so there we would say that if a reloc always implies a function
call, we should always use the PLT if there is one.  We could do by
passing a flag to use_plt_offset, or we could do that instead of calling
use_plt_offset.  I guess the advantage of passing a flag is that it is
more likely to be done right for a new target.

> On targets like x86_64 that _do_ have this distinction, we've
> already honoured that distinction when deciding whether to create
> a PLT in the first place.  Is there actually any harm in resolving
> a R_X86_64_PC32 to a PLT if a PLT had already been created for
> other reasons?

The R_X86_64_PC32 reloc is generated for instructions which are not
function calls, such as references to global variables when using the
(default) small memory model.

Ian
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