Fix UB in SIMD dot product arithmetic #8234
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stevenfontanella
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kripken
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Jan 27, 2026
| switch (type.getBasic()) { | ||
| case Type::i32: | ||
| return Literal(uint32_t(i32) + uint32_t(other.i32)); | ||
| return Literal(bit_cast<uint32_t>(i32) + bit_cast<uint32_t>(other.i32)); |
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I am getting en.cppreference.com took too long to respond so I can't read the docs on this, but is bit_cast not from a pretty recent C++ version? Is it not too new?
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bit_cast is from C++20 but we polyfill it with our own implementation: link. utilities.h is included in this file and bit_cast is already used in other places in this file.
kripken
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tlively
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From reading the code, most other arithmetic in Literal.cpp shouldn't invoke UB. There are some spec tests that are disabled due to float/nan behavior that I'll look at in future PRs.