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Date: Thu, 20 Nov 2014 08:14:24 +0200
From: Timo Teras <>
To: Isaac Dunham <>
Subject: Re: webkitfltk segfaults in do_relocs

On Wed, 19 Nov 2014 14:43:40 -0800
Isaac Dunham <> wrote:

> On Wed, Nov 19, 2014 at 03:56:35PM -0500, Rich Felker wrote:
> > Got it. The line number in your original report seems to be off by a
> > bit (it points to TLSDESC related cases) but I've found the
> > offending relocation(s):
> > 
> > 0083deea  0000c402 R_386_PC32        00000000   exp
> > 0083df03  00010a02 R_386_PC32        00000000   log
> > 0083df1c  00030502 R_386_PC32        00000000   floor
> > 0083df35  00024502 R_386_PC32        00000000   ceil
> > 
> > I have no idea why the linker is emitting these. It should have
> > resolved them at ld time to PLT entries in the main program's PLT,
> > but maybe since you're building as PIE (this is defautl on Alpine)
> > that doesn't happen (this would be a linker bug, IMO). If it were
> > going to do this (leave the relocations in the output), it should
> > mark the program as DT_TEXTREL (having textrels), but this is
> > probably suppressed for PIE because it's not supposed to happen.

See also the following link on how to figure out where textrels come

> > My best guess as to what's triggering the problem is that there's
> > some nasty asm or other hacks that are not PIE-compatible somewhere
> > in the program. It's also possible that you're pulling in static
> > libraries (which would not be PIE-compatible) due to not having the
> > dynamic version of a needed library installed.
> All external libs are available in shared format, except perhaps -lgcc
> But the whole library is built in static form only, without -fPIC.

You need -fPIC for PIE-linking. Missing -fPIC is likely cause for this.

If there's some weird reason to not use -fPIC, you probably also need
to link the executable with -fno-PIE, but this means the main DSO will
not be included in address space layout randomization.


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