acc6bcdc50
With -fpatchable-function-entry (or the patchable_function_entry function attribute), we emit records of patchable entry locations to the __patchable_function_entries section. Add an additional parameter to the command line option that allows one to specify a different default section name for the records, and an identical parameter to the function attribute that allows one to override the section used. The main use case for this change is the Linux kernel using prefix NOPs for ftrace, and thus depending on__patchable_function_entries to locate traceable functions. Functions that are not traceable currently disable entry NOPs using the function attribute, but this creates a compatibility issue with -fsanitize=kcfi, which expects all indirectly callable functions to have a type hash prefix at the same offset from the function entry. Adding a section parameter would allow the kernel to distinguish between traceable and non-traceable functions by adding entry records to separate sections while maintaining a stable function prefix layout for all functions. LKML discussion: https://lore.kernel.org/lkml/Y1QEzk%2FA41PKLEPe@hirez.programming.kicks-ass.net/
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: