Fix debug infos of nested variables

[kinke]

No description provided.

[kinke]

Sadly, it doesn't get rid of #930 at the same time. May really be an LLVM bug after all. ;)

[dnadlinger]

Whoops, was too quick in pressing the merge button, only the AppVeyor status was showing up. Let's hope I didn't break the Travis build.

[kinke]

Heh, no worries. :)
I've run dmd-testsuite-debug in both x64 and x86 on Linux (with LLVM 3.7), non-QUICK. There's only a single remaining issue, in 32-bit:

 ... runnable/mars1.d               (-inline -release -gc -O -fPIC)
Test failed.  The logged output:
/home/martin/build-ldc/bin/ldmd2 -conf= -m32 -Irunnable   -od/home/martin/build-ldc/dmd-testsuite-debug-32/runnable -of/home/martin/build-ldc/dmd-testsuite-debug-32/runnable/mars1_0 runnable/mars1.d
ldc2: /home/martin/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:1130: llvm::SDValue llvm::SelectionDAG::getConstant(uint64_t, llvm::SDLoc, llvm::EVT, bool, bool): Assertion `(EltVT.getSizeInBits() >= 64 || (uint64_t)((int64_t)Val >> EltVT.getSizeInBits()) + 1 < 2) && "getConstant with a uint64_t value that doesn't fit in the type!"' failed.
#0 0x147b948 printSymbolizedStackTrace /home/martin/llvm/lib/Support/Unix/Signals.inc:346:0
#1 0x147b948 llvm::sys::PrintStackTrace(llvm::raw_ostream&) /home/martin/llvm/lib/Support/Unix/Signals.inc:438:0
#2 0x147aa89 SignalHandler(int) /home/martin/llvm/lib/Support/Unix/Signals.inc:210:0
#3 0x2af4d7b8c340 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x10340)
#4 0x2af4d8a0dcc9 gsignal /build/buildd/eglibc-2.19/signal/../nptl/sysdeps/unix/sysv/linux/raise.c:56:0
#5 0x2af4d8a110d8 abort /build/buildd/eglibc-2.19/stdlib/abort.c:91:0
#6 0x2af4d8a06b86 __assert_fail_base /build/buildd/eglibc-2.19/assert/assert.c:92:0
#7 0x2af4d8a06c32 (/lib/x86_64-linux-gnu/libc.so.6+0x2fc32)
#8 0xaadcf7 APInt /home/martin/llvm/include/llvm/ADT/APInt.h:238:0
#9 0xaadcf7 llvm::SelectionDAG::getConstant(unsigned long, llvm::SDLoc, llvm::EVT, bool, bool) /home/martin/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:1131:0
#10 0x963996 llvm::X86TargetLowering::LowerReturn(llvm::SDValue, unsigned int, bool, llvm::SmallVectorImpl<llvm::ISD::OutputArg> const&, llvm::SmallVectorImpl<llvm::SDValue> const&, llvm::SDLoc, llvm::SelectionDAG&) const /home/martin/llvm/lib/Target/X86/X86ISelLowering.cpp:2013:0
#11 0xadeb4f llvm::SelectionDAGBuilder::visitRet(llvm::ReturnInst const&) /home/martin/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:1274:0
#12 0xb01c2a llvm::Value::getValueID() const /home/martin/llvm/include/llvm/IR/Value.h:363:0
#13 0xb01c2a llvm::Instruction::getOpcode() const /home/martin/llvm/include/llvm/IR/Instruction.h:112:0
#14 0xb01c2a llvm::Instruction::isTerminator() const /home/martin/llvm/include/llvm/IR/Instruction.h:115:0
#15 0xb01c2a llvm::TerminatorInst::classof(llvm::Instruction const*) /home/martin/llvm/include/llvm/IR/InstrTypes.h:73:0
#16 0xb01c2a llvm::isa_impl<llvm::TerminatorInst, llvm::Instruction, void>::doit(llvm::Instruction const&) /home/martin/llvm/include/llvm/Support/Casting.h:56:0
#17 0xb01c2a llvm::isa_impl_cl<llvm::TerminatorInst, llvm::Instruction const*>::doit(llvm::Instruction const*) /home/martin/llvm/include/llvm/Support/Casting.h:96:0
#18 0xb01c2a llvm::isa_impl_wrap<llvm::TerminatorInst, llvm::Instruction const*, llvm::Instruction const*>::doit(llvm::Instruction const* const&) /home/martin/llvm/include/llvm/Support/Casting.h:122:0
#19 0xb01c2a llvm::isa_impl_wrap<llvm::TerminatorInst, llvm::Instruction const* const, llvm::Instruction const*>::doit(llvm::Instruction const* const&) /home/martin/llvm/include/llvm/Support/Casting.h:114:0
#20 0xb01c2a isa<llvm::TerminatorInst, const llvm::Instruction*> /home/martin/llvm/include/llvm/Support/Casting.h:134:0
#21 0xb01c2a llvm::SelectionDAGBuilder::visit(llvm::Instruction const&) /home/martin/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:910:0
#22 0xb10ab1 llvm::SelectionDAGISel::SelectBasicBlock(llvm::ilist_iterator<llvm::Instruction const>, llvm::ilist_iterator<llvm::Instruction const>, bool&) /home/martin/llvm/include/llvm/ADT/ilist.h:60:0
#23 0xb1418e llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) /home/martin/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:1317:0
#24 0xb16249 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) /home/martin/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:465:0
#25 0x922114 (anonymous namespace)::X86DAGToDAGISel::runOnMachineFunction(llvm::MachineFunction&) /home/martin/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp:175:0
#26 0x13cd680 llvm::FPPassManager::runOnFunction(llvm::Function&) /home/martin/llvm/lib/IR/LegacyPassManager.cpp:1520:0
#27 0x13cda1b llvm::FPPassManager::runOnModule(llvm::Module&) /home/martin/llvm/include/llvm/ADT/ilist.h:58:0
#28 0x13cdd14 runOnModule /home/martin/llvm/lib/IR/LegacyPassManager.cpp:1596:0
#29 0x13cdd14 llvm::legacy::PassManagerImpl::run(llvm::Module&) /home/martin/llvm/lib/IR/LegacyPassManager.cpp:1698:0
#30 0x620684 codegenModule(llvm::TargetMachine&, llvm::Module&, llvm::raw_fd_ostream&, llvm::TargetMachine::CodeGenFileType) /home/martin/ldc/driver/toobj.cpp:130:0
#31 0x620877 writeModule(llvm::Module*, std::string) /home/martin/ldc/driver/toobj.cpp:593:0
#32 0x61b2bb std::string::_M_data() const /usr/include/c++/4.8/bits/basic_string.h:293:0
#33 0x61b2bb std::string::_M_rep() const /usr/include/c++/4.8/bits/basic_string.h:301:0
#34 0x61b2bb ~basic_string /usr/include/c++/4.8/bits/basic_string.h:539:0
#35 0x61b2bb ldc::CodeGenerator::writeAndFreeLLModule(char const*) /home/martin/ldc/driver/codegenerator.cpp:171:0
#36 0x5ef398 main /home/martin/ldc/driver/main.cpp:1323:0
#37 0x2af4d89f8ec5 __libc_start_main /build/buildd/eglibc-2.19/csu/libc-start.c:321:0
#38 0x615bef _start (/home/martin/build-ldc/bin/ldc2+0x615bef)

[kinke]

Same picture with dmd-testsuite in release config: no failures on x64, the same ICE on x86.