Fix undefined behavior in line drawing.#21512
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opencv-pushbot merged 1 commit intoopencv:3.4from Jan 25, 2022
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Left shift of negative values is undefined.
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Left shift of negative values is undefined but works in practice. A test is useless as there is no UBSAN on the build farm. This is a follow-up on https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=44270 and https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=44386 The pull request opencv#21512 was incomplete.
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vrabaud
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Left shift of negative values is undefined but works in practice. A test is useless as there is no UBSAN on the build farm. This is a follow-up on https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=44270 and https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=44386 The pull request opencv#21512 was incomplete.
vrabaud
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https://godbolt.org/z/zhcj4h1xz Left shift of negative values is implementation defined. We make sure that we always shift a positive. A test is useless as there is no UBSAN on the build farm. This is a follow-up on https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=44270 and https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=44386 The pull request opencv#21512 was incomplete.
vrabaud
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Feb 9, 2022
https://godbolt.org/z/zhcj4h1xz Left shift of negative values is implementation defined. We make sure that we always shift a positive. A test is useless as there is no UBSAN on the build farm. This is a follow-up on https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=44270 and https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=44386 The pull request opencv#21512 was incomplete.
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Left shift of negative values is undefined but works in practice.
A test is useless as there is no MSAN on the build farm.
This is a follow-up on https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=40230
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