[LLVMdev] New strict-aliasing warning?

[Hal Finkel]

When compiling trunk using gcc 4.1.2 on linux/ppc64, I now see a warning
that I don't remember seeing previously:

llvm[2]: Compiling InlineSpiller.cpp for Release+Asserts build
/src/llvm-trunk-dev/include/llvm/ADT/PointerIntPair.h: In member
function ‘const PointerTy* llvm::PointerIntPair<PointerTy, IntBits,
IntType, PtrTraits>::getAddrOfPointer() const [with PointerTy = void*,
unsigned int IntBits = 1u, IntType = bool, PtrTraits =
llvm::PointerUnionUIntTraits<llvm::VNInfo*,
llvm::SmallVector<llvm::VNInfo*, 4u>*>]’:
/src/llvm-trunk-dev/include/llvm/ADT/PointerUnion.h:153:   instantiated
from ‘const PT1* llvm::PointerUnion<PT1, PT2>::getAddrOf() const [with T
= llvm::VNInfo*, PT1 = llvm::VNInfo*, PT2 =
llvm::SmallVector<llvm::VNInfo*, 4u>*]’
/src/llvm-trunk-dev/include/llvm/ADT/TinyPtrVector.h:63:   instantiated
from ‘const EltTy* llvm::TinyPtrVector<EltTy>::begin() const [with EltTy
= llvm::VNInfo*]’
/src/llvm-trunk-dev/lib/CodeGen/InlineSpiller.cpp:382:   instantiated
from here
/src/llvm-trunk-dev/include/llvm/ADT/PointerIntPair.h:98: warning:
dereferencing type-punned pointer will break strict-aliasing rules

I think that this might be indicating some kind of problem because I am
also currently seeing a crash in InlineSpiller on linux/ppc64. I am not
yet sure if the crash and this warning are related. Does anyone know why
this warning has appeared?

Thanks again,
Hal

-- 
Hal Finkel
Postdoctoral Appointee
Leadership Computing Facility
Argonne National Laboratory