fix thinko in tree-emutls, breaking tls support on vxworks

fix thinko in tree-emutls, breaking tls support on vxworks

[Olivier Hainque]

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Hello,

With the current mainline configured for powerpc-wrs-vxworks,
compiling the source below exposes a problem with tls support
(emulated) on this target:

  /* t.c  */
  __thread int y = 2;

./cc1 t.c -o -

 t.c:1:14: error: __tls__y causes a section type conflict with y
 __thread int y = 2;
              ^
 t.c:1:14: note: ‘y’ was declared here
   .section .tls_data,"a",@progbits
   .align 2
   .type y, @object
   .size y, 4
 y:
   .long 2
   .globl __tls__y
   .align 2
   .type __tls__y, @object
   .size __tls__y, 12
 __tls__y:
   .long y
   .long 0
   .long 4

The error is unexpected and we observe that both "y"
and "__tls_y" are emitted in the .tls_data section despite

    targetm.emutls.var_section = ".tls_vars";

in vxworks_override_option.

This looks like a simple thinko in tree-emutls.c, which
this patch fixes.

I checked that the VxWorks compiler behaves as expected after the
patch (no error + __tls_y emitted in .tls_vars). Also bootstrapped
and regression tested on x86_64-linux.

OK to commit ?

Thanks in advance,

With Kind Regards,

Olivier

2012-07-03  Olivier Hainque  <hainque@adacore.com>

        * tree-emutls.c (new_emutls_decl): When a var_section is requested by
        the target, attach the new decl to that, not to the template section.


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*** /tmp/BV69pV_tree-emutls.c	2012-07-03 11:13:13.546593377 +0200
--- gcc/tree-emutls.c	2012-06-28 15:10:47.286383962 +0200
*************** new_emutls_decl (tree decl, tree alias_o
*** 312,319 ****
    if (!DECL_COMMON (to) && targetm.emutls.var_section)
      {
        DECL_SECTION_NAME (to)
!         = build_string (strlen (targetm.emutls.tmpl_section),
! 			targetm.emutls.tmpl_section);
      }
  
    /* If this variable is defined locally, then we need to initialize the
--- 312,319 ----
    if (!DECL_COMMON (to) && targetm.emutls.var_section)
      {
        DECL_SECTION_NAME (to)
!         = build_string (strlen (targetm.emutls.var_section),
! 			targetm.emutls.var_section);
      }
  
    /* If this variable is defined locally, then we need to initialize the

Re: fix thinko in tree-emutls, breaking tls support on vxworks

[Richard Henderson]

On 07/03/2012 02:09 AM, Olivier Hainque wrote:
> 2012-07-03  Olivier Hainque  <hainque@adacore.com>
> 
>         * tree-emutls.c (new_emutls_decl): When a var_section is requested by
>         the target, attach the new decl to that, not to the template section.


Ok.


r~

Re: fix thinko in tree-emutls, breaking tls support on vxworks

[Olivier Hainque]

On Jul 16, 2012, at 19:48 , Richard Henderson wrote:
>>        * tree-emutls.c (new_emutls_decl): When a var_section is requested by
>>        the target, attach the new decl to that, not to the template section.
> 
> Ok.

rev 190179, after a couple of weeks off.

Thanks :)