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Subject: Re: how do i cross build world/kernel with clang?
From: David Chisnall <theraven@FreeBSD.org>
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Date: Mon, 2 Sep 2013 08:47:26 +0100
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To: John-Mark Gurney <jmg@funkthat.com>
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On 2 Sep 2013, at 03:01, John-Mark Gurney <jmg@funkthat.com> wrote:

> b/crtn.o: warning: linking PIC files with non-PIC files

I think that this is an issue in our import of clang.  I'll have to =
check whether I upstreamed the code, but it's basically just not setting =
the e_flags field in the ELF header correctly (this required a little =
bit of tweaking in LLVM, because MIPS is the only platform that uses =
e_flags in quite this way - for everything else you know what the value =
should be from the target triple).

> exect.So: In function `exect':
> (.text+0x18): relocation truncated to fit: R_MIPS_PC16 against =
`__cerror'

I believe that this is a limitation of our ld.  The PC16 relocation =
ought to be made to point to a PLT entry if it's too close, but it is =
just being truncated instead.  This is fixed in upstream ld-bfd, and =
hopefully will be easy to fix with MCLinker if it doesn't already work.  =
I'll see if we can make clang default to using larger relocation types =
for things not in the same compilation unit.

David