The linker is refusing to link linkonce globals to externally visible globals. 
This is wrong, it should just drop the linkonce global like it does for weak
symbols.

This is tested by Linker/2003-10-27-LinkOncePromote.ll

This does not really effect 1.0, because the C/C++ front-end never produced
linkonce globals.

This is now fixed:
http://mail.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20031027/008864.html

Stacker produces linkonce globals and this bug is not resolved in 1.3.

The attached test case is reduced from a two bytecode files: the prime.st file
compiled to bytecode and the stacker runtime compiled to bytecode. One declares
that _stack_ variable extern, the other declares it linkonce. 

Attempting to run this with lli produces:
Could not resolve external global address: _stack_
lli((anonymous namespace)::PrintStackTrace()+0x1a)[0x85633e6]
lli((anonymous namespace)::SignalHandler(int)+0xc7)[0x8563653]
/lib/tls/libc.so.6[0x420277b8]
/lib/tls/libc.so.6(abort+0x1d5)[0x42028c55]
lli(llvm::JIT::getOrEmitGlobalVariable(llvm::GlobalVariable const*)+0xad)[0x83262fb]
lli((anonymous
namespace)::Emitter::getGlobalValueAddress(llvm::GlobalValue*)+0x59)[0x83243f3]
lli((anonymous
namespace)::Emitter::emitGlobalAddressForPtr(llvm::GlobalValue*)+0x25)[0x838a13f]
lli((anonymous namespace)::Emitter::emitInstruction(llvm::MachineInstr
const&)+0x5a7)[0x838afc7]
lli((anonymous namespace)::Emitter::emitBasicBlock(llvm::MachineBasicBlock
const&)+0xaa)[0x8389f70]
lli((anonymous
namespace)::Emitter::runOnMachineFunction(llvm::MachineFunction&)+0xc6)[0x8389dd4]
lli(llvm::MachineFunctionPass::runOnFunction(llvm::Function&)+0x29)[0x8347df1]
lli(llvm::PassManagerTraits<llvm::Function>::runPass(llvm::FunctionPass*,
llvm::Function*)+0x1f)[0x84db56f]
lli(llvm::PassManagerT<llvm::Function>::runOnUnit(llvm::Function*)+0x5c0)[0x84dae2c]
lli(llvm::PassManagerTraits<llvm::Function>::runOnFunction(llvm::Function&)+0x1f)[0x84dbaa1]
lli(llvm::FunctionPass::run(llvm::Function&)+0x6a)[0x848314a]
lli(llvm::FunctionPassManager::run(llvm::Function&)+0xe7)[0x84826e9]
lli(llvm::JIT::runJITOnFunction(llvm::Function*)+0x4f)[0x8325fcb]
lli(llvm::JIT::getPointerToFunction(llvm::Function*)+0x15f)[0x832617b]
lli(llvm::JIT::runFunction(llvm::Function*, std::vector<llvm::GenericValue,
std::allocator<llvm::GenericValue> > const&)+0x4e)[0x8325254]
lli(llvm::ExecutionEngine::runFunctionAsMain(llvm::Function*,
std::vector<std::basic_string<char, std::char_traits<char>, std::allocator<char>
>, std::allocator<std::basic_string<char, std::char_traits<char>,
std::allocator<char> > > > const&, char const* const*)+0x2ee)[0x8377ef6]
lli(main+0x2dd)[0x830abb1]
/lib/tls/libc.so.6(__libc_start_main+0xe4)[0x42015704]
lli(dlopen+0x41)[0x830a731]
Aborted (core dumped)

Compiling the file with llc produces the following x86 assembly:
        .intel_syntax
 
 
        .text
        .align  16
        .globl  main
        .type   main, @function
main:
.LBBmain_0:     #
        mov %EAX, OFFSET _stack_
        mov %EAX, DWORD PTR [%EAX]
        #IMPLICIT_USE
        ret
 
 
        .data
        .comm l1__stack_,8192,4         # [2048 x int]* %_stack_

Which, if you try to link it, produces:
bash-2.05b$ gcc prime.s -o prime
/tmp/cc1blvtd.o(.text+0x1): In function `main':
: undefined reference to `_stack_'
collect2: ld returned 1 exit status

Created an attachment (id=171) [details]
Test Case Showing Bug Not Resolved

A reduced test case from a Stacker compile.

This bug shouldn't be reopened, as this is a different issue than the original
PR.  If you think there's a bug, please refile as a new one.  You might try to
run the -funcresolve pass on this testcase, it will probably do what you want.

Note that the real solution to this problem is to fix bug 411.

-Chris