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Comment by bitcharmer | Hacker News Reader

This is a great step forward. Compiling with clang will allow kernel developers to run code checks and analysis unavailable to gcc.

This will definitely have a positive effect on code quality.

Not even mentioning it should be a little bit easier to configure IDEs like CLion for working with Linux source tree.

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Is there a list of checks and analysis that you can't do from a gcc pipeline?

Maybe he's talking about the sanitizers? eg: https://clang.llvm.org/docs/AddressSanitizer.html

Those sanitizers are present in gcc too[0].

[0] https://gcc.gnu.org/onlinedocs/gcc/Instrumentation-Options.h...

ah! thanks

Present != Equal, feature wise. Not by a long shot. At the same conf, one of my friends who develops the sanitizers said it's easier to develop for LLVM, so that's where Dev work is done.

> Present != Equal, feature wise.

It is developed by google[0] afaik. The link says it is present in LLVM and gcc. I don't know what makes the difference (may be License?). On the contrary I have felt gcc better for my work. I have been following a clang bug[1] for long and have seen no fix so far.

[0] https://github.com/google/sanitizers/wiki/AddressSanitizer

[1] https://bugs.llvm.org/show_bug.cgi?id=23910

Clang has better support for plugins and calling it as a library; that sort of thing was resisted by GCC. Google has a bunch of large-scale tooling based on the Clang frontend which AFAIK wouldn't be possible with GCC.

sure sure, but today (and even two years ago) you can add -fsanitize={address,undefined,etc} on both clang and gcc. So this does not answer the question.

All sanitizers are also available in GCC, so no.

Are you sure? Last time I checked the ones llvm had and gcc did not were:

Dynamic alloca overflow detection

Symbol size changing for global variables

Adaptive global redzone sizes

Invalid pointer pairs detection

Support for no_sanitize attribute

Support for dead stripping of globals on Linux

I might be out of date on some or even all, so please correct me where I'm wrong. Thank you in advance.

Wrong. Not all kernel versions.

Sanitizers are run-time tools; I'd be surprised if any of them worked out of the box with the kernel.

Address sanitizer was "ported" to the kernel a while ago; not sure if UBSAN is or will be in the future.

There are kernel versions. KASAN, KUBSAN, KMSAN.

the static analyzer, along with all the other checks available from clang-tidy: https://clang.llvm.org/extra/clang-tidy/checks/list.html

I'm surprised there is a static analyzer available for clang that isn't somewhat equivalently offered in gcc toolchains. I guess I'm assuming folks would be using something like Coverity for major static analysis.

Specifically, this sounds like it is just preferring the other toolchain. Are there literally things that don't have equivalents?

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