[Bug ipa/59469] [4.8/4.9 Regression] LLVM build failure with gcc LTO

["trippels at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59469

--- Comment #37 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
I think the error is that the symbol from the explicit template instantiation
in Function.ii (marked with forced_by_abi) gets merged with the symbol in the
same COMDAT group from BasicBlock.ii. (This symbol isn't marked with
forced_by_abi, but somehow has prevailing_def_ironly_exp)

Merging nodes for
_ZN4llvm21SymbolTableListTraitsINS_10BasicBlockENS_8FunctionEE21transferNodesFromListERNS_12ilist_traitsIS1_EENS_14ilist_iteratorIS1_EES8_.
Candidates:
_ZN4llvm21SymbolTableListTraitsINS_10BasicBlockENS_8FunctionEE21transferNodesFromListERNS_12ilist_traitsIS1_EENS_14ilist_iteratorIS1_EES8_/9
(transferNodesFromList) @0x7f4d65008e18
  Type: function definition analyzed
  Visibility: externally_visible prevailing_def_ironly_exp public weak comdat
comdat_group:_ZN4llvm21SymbolTableListTraitsINS_10BasicBlockENS_8FunctionEE21transferNodesFromLi
stERNS_12ilist_traitsIS1_EENS_14ilist_iteratorIS1_EES8_ one_only
  next sharing asm name: 22
  References: 
  Referring: 
  Read from file: /tmp/ccx3oVJ3.o
  First run: 0
  Function flags:
  Called by: _ZN4llvm10BasicBlock10moveBeforeEv/1 (1.00 per call) (can throw
external) _ZN4llvm10BasicBlock10moveBeforeEv/1 (1.00 per call) (can throw
external) 
  Calls: _ZN4llvm14ilist_iteratorINS_10BasicBlockEEneERS2_/16 (11.11 per call)
(can throw external) _ZN4llvm14ilist_iteratorINS_10BasicBlockEEppEv/15 (10.11
per call) (can throw external)
_ZN4llvm12ilist_traitsINS_10BasicBlockEE9getSymTabEPNS_8FunctionE/14 (1.00 per
call) (can throw external)
_ZN4llvm21SymbolTableListTraitsINS_10BasicBlockENS_8Fu
nctionEE12getListOwnerEv/13 (1.00 per call) (can throw external)
_ZN4llvm21SymbolTableListTraitsINS_10BasicBlockENS_8FunctionEE12getListOwnerEv/13
(1.00 per call) (can throw 
external) 
_ZN4llvm21SymbolTableListTraitsINS_10BasicBlockENS_8FunctionEE21transferNodesFromListERNS_12ilist_traitsIS1_EENS_14ilist_iteratorIS1_EES8_/22
(transferNodesFromList) @0x7f4d651888f8
  Type: function definition analyzed
  Visibility: forced_by_abi externally_visible preempted_ir public weak
comdat_group:_ZN4llvm21SymbolTableListTraitsINS_10BasicBlockENS_8FunctionEE21transferNodesFromListERNS
_12ilist_traitsIS1_EENS_14ilist_iteratorIS1_EES8_ one_only
  previous sharing asm name: 9
  References: 
  Referring: 
  Read from file: /tmp/ccZVoWfZ.o
  First run: 0
  Function flags:
  Called by: 
  Calls: