[Bug middle-end/50598] [4.7 Regression] Undefined symbols: "___emutls_v.*", ... on *-apple-darwin*

[iains at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50598

--- Comment #8 from Iain Sandoe <iains at gcc dot gnu.org> 2011-11-04 08:56:36 
UTC ---
the following also fails (for both c and c++):

extern __thread int i;

__thread int i;

===
 - producing an empty asm file
===

gcc-4.6 produces:

        .globl ___emutls_v.i
        .data
        .align 2
___emutls_v.i:
        .long   4
        .long   4
        .long   0
        .long   0
       .constructor
        .destructor 
        .align 1
        .subsections_via_symbols

====

I'm wondering if, when the variables are pruned - if they are emutls proxies,
they need to check whether the parent var is prune-able. 

 I looked at tree-emutls.c and it seems that the proxy variable should (in
principle) be inheriting the attributes (including external and public) of the
thread var.   Perhaps they are missed in some update.