
This has been a long-standing problem, but we didn't use to call the destructors of items on the stack unless we explicitly `pop()` or `discard()` them. When interpretation was interrupted midway-through (because something failed), we left `Pointer`s on the stack. Since all `Block`s track what `Pointer`s point to them (via a doubly-linked list in the `Pointer`), that meant we potentially leave deallocated pointers in that list. We used to work around this by removing the `Pointer` from the list before deallocating the block. However, we now want to track pointers to global blocks as well, which poses a problem since the blocks are never deallocated and thus those pointers are always left dangling. I've tried a few different approaches to fixing this but in the end I just gave up on the idea of never knowing what items are in the stack. We already have an `ItemTypes` vector that we use for debugging assertions. This patch simply enables this vector unconditionally and uses it in the abort case to properly `discard()` all elements from the stack. That's a little sad IMO but I don't know of another way of solving this problem. As expected, this is a slight hit to compile times: https://llvm-compile-time-tracker.com/compare.php?from=574d0a92060bf4808776b7a0239ffe91a092b15d&to=0317105f559093cfb909bfb01857a6b837991940&stat=instructions:u
C language Family Front-end
Welcome to Clang.
This is a compiler front-end for the C family of languages (C, C++ and Objective-C) which is built as part of the LLVM compiler infrastructure project.
Unlike many other compiler frontends, Clang is useful for a number of things beyond just compiling code: we intend for Clang to be host to a number of different source-level tools. One example of this is the Clang Static Analyzer.
If you're interested in more (including how to build Clang) it is best to read the relevant websites. Here are some pointers:
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Information on Clang: http://clang.llvm.org/
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Building and using Clang: http://clang.llvm.org/get_started.html
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Clang Static Analyzer: http://clang-analyzer.llvm.org/
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Information on the LLVM project: http://llvm.org/
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If you have questions or comments about Clang, a great place to discuss them is on the Clang forums:
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If you find a bug in Clang, please file it in the LLVM bug tracker: