forked from OSchip/llvm-project
5bd31b37ca
of casting the integer '4' to such a pointer. There is no reason to expect '4' to be a portable or reliable pointer of this form. The only reason this ever worked is because the PointerIntPair that this actually gets used with has an artificially *low* presumed alignment that allowed it to work. When the alignment of PointerIntPair is derived from the actual type's alignment, the asserts start firing on this pointer. I'm amazed we never managed to do anything that triggered the alignment sanitizer with it, as this is just flat out UB. If folks dislike this approach to providing a sentinel fragment address, there are a myriad of other alternatives, suggestions welcome. But this one has the distinct advantage of not requiring the friend dance of ilist's sentinel (which I'll point out is *also* in play for MCFragment!) and seems to be using a nicely provided facility in MCFragment to establish just such dummy nodes. This is part of a series of patches to allow LLVM to check for complete pointee types when computing its pointer traits. This is absolutely necessary to get correct (or reproducible) results for things like how many low bits are guaranteed to be zero. llvm-svn: 256552 |
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| clang | ||
| clang-tools-extra | ||
| compiler-rt | ||
| debuginfo-tests | ||
| libclc | ||
| libcxx | ||
| libcxxabi | ||
| libunwind | ||
| lld | ||
| lldb | ||
| llgo | ||
| llvm | ||
| openmp | ||
| polly | ||