[RFC PATCH] Don't use ELF weak for entities with vague linkage when COMDAT groups are available

[Andrew Haley]

Julian Brown writes:
 > Hi,
 > 
 > This is a patch to disable ELF weak for entities with vague linkage when 
 > HAVE_GAS_COMDAT_GROUP is true. It was previously posted in two parts and 
 > applied, then reverted soon after for causing breakage:
 > 
 > elfos.h patch:
 >    http://gcc.gnu.org/ml/gcc-patches/2005-02/msg01624.html
 > 
 > Java patch:
 >    http://gcc.gnu.org/ml/gcc-patches/2005-03/msg00712.html
 > 
 > 
 > If people would try this patch and run the testsuite on their machines, 
 > I'd be grateful. I'd appreciate it if you post information about 
 > failures which show up for you, with version numbers of binutils bits, 
 > so I can attempt to track down whatever broke before.

This patch breaks indirect dispatch with PIC.  With some files, I'm
now getting errors of the form

jacorb.s:9882754: Error: can't resolve `.gnu.linkonce.t._ZN3org3omg21CosNotifyChannelAdmin22_ProxyPushSupplierStub15lifetime_filterEv' {.gnu.linkonce.t._ZN3org3omg21CosNotifyChannelAdmin22_ProxyPushSupplierStub15lifetime_filterEv section} - `.Ltext0' {.text section}

Andrew.