
This patch is part of a series to support driver managed module builds for C++ named modules and Clang modules. This introduces a scanner that detects C++ named module usage early in the driver with only negligible overhead. For now, it is enabled only with the `-fmodules-driver` flag and serves solely diagnostic purposes. In the future, the scanner will be enabled for any (modules-driver compatible) compilation with two or more inputs, and will help the driver determine whether to implicitly enable the modules driver. Since the scanner adds very little overhead, we are also exploring enabling it for compilations with only a single input. This approach could allow us to detect `import std` usage in a single-file compilation, which would then activate the modules driver. For performance measurements on this, see https://github.com/naveen-seth/llvm-dev-cxx-modules-check-benchmark. RFC for driver managed module builds: https://discourse.llvm.org/t/rfc-modules-support-simple-c-20-modules-use-from-the-clang-driver-without-a-build-system This patch relands the reland (2d31fc8) for commit ded1426. The earlier reland failed due to a missing link dependency on `clangLex`. This reland fixes the issue by adding the link dependency after discussing it in the following RFC: https://discourse.llvm.org/t/rfc-driver-link-the-driver-against-clangdependencyscanning-clangast-clangfrontend-clangserialization-and-clanglex
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: