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A comment on Closing the gap: cross-language LTO between Rust and C/C++. Parent comment

Re:Closing the gap: cross-language LTO between Rust and C/C++ by sanxiyn on Thursday September 19, 2019 @09:21PM (#21022460)
Another: Rust is de facto QA service for LLVM's support for overflow intrinsics. Unlike noalias they continue to work, but in practice they continue to work only due to fixes from Rust project.
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Re:Closing the gap: cross-language LTO between Rust and C/C++ by ridiculous_fish on Thursday September 19, 2019 @09:41PM (#21022558)
Why doesn't Swift play that role?
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Re:Closing the gap: cross-language LTO between Rust and C/C++ by sanxiyn on Thursday September 19, 2019 @09:44PM (#21022580)
In fact I am not sure why... I am just reporting the experience. Maybe because of architectural coverage, because while bugs also happen in architecture-independent optimizations, more bugs happen in, say, PowerPC backend.

Edit: Another possibility is difference between how often Rust and Swift update to LLVM trunk. Both have LLVM fork pinned to specific version updated from time to time and I guess the first to update gets all the bugs.

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Re:Closing the gap: cross-language LTO between Rust and C/C++ by masklinn on Friday September 20, 2019 @01:45AM (#21023610)
Possibly because Swift being more of an application language, Swift codebases in general have very little use for overflowing operations?
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Re:Closing the gap: cross-language LTO between Rust and C/C++ by sanxiyn on Friday September 20, 2019 @04:49AM (#21024528)
No, it's not that. All Swift arithmetic compiles to overflow intrinsics.
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