forked from OSchip/llvm-project
460ce58fa6
Previously, __weak was silently accepted and ignored in MRC mode. That makes this a potentially source-breaking change that we have to roll out cautiously. Accordingly, for the time being, actual support for __weak references in MRC is experimental, and the compiler will reject attempts to actually form such references. The intent is to eventually enable the feature by default in all non-GC modes. (It is, of course, incompatible with ObjC GC's interpretation of __weak.) If you like, you can enable this feature with -Xclang -fobjc-weak but like any -Xclang option, this option may be removed at any point, e.g. if/when it is eventually enabled by default. This patch also enables the use of the ARC __unsafe_unretained qualifier in MRC. Unlike __weak, this is being enabled immediately. Since variables are essentially __unsafe_unretained by default in MRC, the only practical uses are (1) communication and (2) changing the default behavior of by-value block capture. As an implementation matter, this means that the ObjC ownership qualifiers may appear in any ObjC language mode, and so this patch removes a number of checks for getLangOpts().ObjCAutoRefCount that were guarding the processing of these qualifiers. I don't expect this to be a significant drain on performance; it may even be faster to just check for these qualifiers directly on a type (since it's probably in a register anyway) than to do N dependent loads to grab the LangOptions. rdar://9674298 llvm-svn: 251041 |
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| include | ||
| lib | ||
| runtime | ||
| test | ||
| tools | ||
| unittests | ||
| utils | ||
| www | ||
| .arcconfig | ||
| .clang-format | ||
| .clang-tidy | ||
| .gitignore | ||
| CMakeLists.txt | ||
| CODE_OWNERS.TXT | ||
| INSTALL.txt | ||
| LICENSE.TXT | ||
| Makefile | ||
| ModuleInfo.txt | ||
| NOTES.txt | ||
| README.txt | ||
README.txt
//===----------------------------------------------------------------------===// // 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.llvm.org/mailman/listinfo/cfe-dev If you find a bug in Clang, please file it in the LLVM bug tracker: http://llvm.org/bugs/