Fix function mod decimal scale overflow
#2462
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| // assert that negation of std::numeric_limits<From>::min() will not result in overflow. | ||
| // TODO: find credible source that describes numeric limits of boost multiprecision *checked* integers. | ||
| static_assert(-std::numeric_limits<From>::max() == std::numeric_limits<From>::min()); |
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interestring, I thought -std::numeric_limits<From>::max() should be larger than std::numeric_limits<From>::min() by 1.
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I was also surprised by the fact. I guess Boost made a deliberate decision on checked fixed precision integers. But I didn't find any evidence in Boost multiprecision doc.
By contrast, Boost says unchecked integers use 2's complement representation in their documents: https://www.boost.org/doc/libs/1_76_0/libs/multiprecision/doc/html/boost_multiprecision/tut/ints/cpp_int.html
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@fuzhe1989, Thanks for your review. The bot only counts LGTMs from Reviewers and higher roles, but you're still welcome to leave your comments. See the corresponding SIG page for more information. Related SIG: tiflash(slack). |
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/run-all-tests |
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/merge |
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/run-all-tests |
riteme
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cherry pick to release-5.0 in PR #2608 |
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cherry pick to release-5.1 in PR #2609 |
What problem does this PR solve?
Problem Summary: #2402 (issue #2318) will overflow in decimal modulo.
What is changed and how it works?
What's Changed: This PR fixes the issue by assign modulo operation to
need_promote_typeinDecimalBinaryOperation.Related changes
pingcap/docs/pingcap/docs-cn:Check List
Tests
Side effects
Release note
MOD(N, M).