Re: [Qemu-devel] [PATCH] sparc-linux-user: Fix missing symbols in .rel/.rela.plt sections

[Aurelien Jarno]

On Sat, Jan 07, 2012 at 10:01:09PM +0100, Aurelien Jarno wrote:
> On Sat, Jan 07, 2012 at 08:36:12PM +0000, Blue Swirl wrote:
> > On Sat, Jan 7, 2012 at 20:16, Aurelien Jarno <address@hidden> wrote:
> > > Fix .rel.plt sections in the output to not only include .rel.plt
> > > sections from the input but also the .rel.iplt sections and to define
> > > the hidden symbols __rel_iplt_start and __rel_iplt_end around
> > > .rel.iplt as otherwise we get undefined references to these when
> > > linking statically to a multiarch enabled libc (using STT_GNU_IFUNC).
> > >
> > > Blue Swirl <address@hidden>
> > > Signed-off-by: Aurelien Jarno <address@hidden>
> > > ---
> > >  sparc.ld |   16 ++++++++++++++--
> > >  1 files changed, 14 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/sparc.ld b/sparc.ld
> > > index 56efe34..e52c3d2 100644
> > > --- a/sparc.ld
> > > +++ b/sparc.ld
> > > @@ -37,8 +37,20 @@ SECTIONS
> > >   .rela.fini     : { *(.rela.fini)      }
> > >   .rel.bss       : { *(.rel.bss)                }
> > >   .rela.bss      : { *(.rela.bss)               }
> > > -  .rel.plt       : { *(.rel.plt)                }
> > > -  .rela.plt      : { *(.rela.plt)               }
> > > +  .rel.plt      :
> > > +  {
> > > +    *(.rel.plt)
> > > +    PROVIDE_HIDDEN (__rel_iplt_start = .);
> > > +    *(.rel.iplt)
> > > +    PROVIDE_HIDDEN (__rel_iplt_end = .);
> > > +  }
> > > +  .rela.plt       :
> > > +  {
> > > +    *(.rela.plt)
> > > +    PROVIDE_HIDDEN (__rela_iplt_start = .);
> > > +    *(.rela.iplt)
> > > +    PROVIDE_HIDDEN (__rela_iplt_end = .);
> > > +  }
> > 
> > PROVIDE_HIDDEN etc. were removed by
> > 8733f6093c2b77502e7228503fc22024e51599b8 in order to support BSDs with
> > older binutils (2.15). Maybe the ld scripts should be generated from a
> > source file for example with CPP, so these lines could be tweaked.
> > 
> 
> It seems this patch was in my local tree for too long, and it seems I
> should have updated it before sending it...
> 
> Other architectures are now using PROVIDE instead of PROVIDE_HIDDEN for 
> __rel{a,}_iplt_{start,end}, so I guess the same can be done for sparc and
> ppc. I am going to do a test build to check that, and I'll come with a
> new patch if it works.

The new patch below also fixes the issue, and uses PROVIDE instead of
PROVIDE_HIDDEN.

sparc-linux-user: Fix missing symbols in .rel/.rela.plt sections

Fix .rel.plt sections in the output to not only include .rel.plt
sections from the input but also the .rel.iplt sections and to define
the hidden symbols __rel_iplt_start and __rel_iplt_end around
.rel.iplt as otherwise we get undefined references to these when
linking statically to a multiarch enabled libc (using STT_GNU_IFUNC).

Cc: Blue Swirl <address@hidden>
Signed-off-by: Aurelien Jarno <address@hidden>
---
 sparc.ld |   16 ++++++++++++++--
 1 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/sparc.ld b/sparc.ld
index 56efe34..cec17c9 100644
--- a/sparc.ld
+++ b/sparc.ld
@@ -37,8 +37,20 @@ SECTIONS
   .rela.fini     : { *(.rela.fini)      }
   .rel.bss       : { *(.rel.bss)                }
   .rela.bss      : { *(.rela.bss)               }
-  .rel.plt       : { *(.rel.plt)                }
-  .rela.plt      : { *(.rela.plt)               }
+  .rel.plt      :
+  {
+    *(.rel.plt)
+    PROVIDE (__rel_iplt_start = .);
+    *(.rel.iplt)
+    PROVIDE (__rel_iplt_end = .);
+  }
+  .rela.plt       :
+  {
+    *(.rela.plt)
+    PROVIDE (__rela_iplt_start = .);
+    *(.rela.iplt)
+    PROVIDE (__rela_iplt_end = .);
+  }
   .init          : { *(.init)   } =0x47ff041f
   .text      :
   {
-- 
1.7.7.3


-- 
Aurelien Jarno                          GPG: 1024D/F1BCDB73
address@hidden                 http://www.aurel32.net