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Re: LTO and asm specs...
From: Richard Henderson <rth@redhat.com>
Date: Tue, 16 Mar 2010 11:31:44 -0700
> On 03/12/2010 09:33 PM, David Miller wrote:
>> I couldn't figure out immediately how to fix this as the
>> way LTO does spec overriding and such looked non-trivial.
>
> It would not be a bad thing, IMO, if the sparc assembler
> were extended to be able to emit any reloc directly, without
> needing a specific command-line option. Then you'd only
> encounter this problem with legacy assemblers.
It's not the assemblers fault.
We're using %hi() and expecting the assembler to emit a
PC relative relcation just because the symbol name happens
to be _GLOBAL_OFFSET_TABLE_ And it will do this, but only
when -PIC. Changing that is pretty dangerous.
But even if we got past that, we need to get the assembler options
right in order to enable instruction classes. For example we have to
get -Av9a there when using VIS instructions.
Other platforms are going to hit things like this too.
LTO really needs to evaluate the specs correctly.