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e7de47efbe
Based on Peter Collingbourne's destructor patches. Prior to this change, clang was considering ?1 to be the complete destructor and the base destructor, which was wrong. This lead to crashes when clang tried to emit two LLVM functions with the same name. In this ABI, TUs with non-inline dtors might not emit a complete destructor. They are emitted as inline thunks in TUs that need them, and they always delegate to the base dtors of the complete class and its virtual bases. This change uses the DeferredDecls machinery to emit complete dtors as needed. Currently in clang try body destructors can catch exceptions thrown by virtual base destructors. In the Microsoft C++ ABI, clang may not have the destructor definition, in which case clang won't wrap the virtual virtual base destructor calls in a try-catch. Diagnosing this in user code is TODO. Finally, for classes that don't use virtual inheritance, MSVC always calls the base destructor (?1) directly. This is a useful code size optimization that avoids emitting lots of extra thunks or aliases. Implementing it also means our existing tests continue to pass, and is consistent with MSVC's output. We can do the same for Itanium by tweaking GetAddrOfCXXDestructor, but it will require further testing. Reviewers: rjmccall CC: cfe-commits Differential Revision: http://llvm-reviews.chandlerc.com/D1066 llvm-svn: 186828
//===----------------------------------------------------------------------===// // C Language Family Front-end //===----------------------------------------------------------------------===// Welcome to Clang. This is a compiler front-end for the C family of languages (C, C++, Objective-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 web sites. Here are some pointers: Information on Clang: http://clang.llvm.org/ Building and using Clang: http://clang.llvm.org/get_started.html Clang Static Analyzer: http://clang-analyzer.llvm.org/ Information on the LLVM project: http://llvm.org/ If you have questions or comments about Clang, a great place to discuss them is on the Clang development mailing list: http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev If you find a bug in Clang, please file it in the LLVM bug tracker: http://llvm.org/bugs/