A decades-old bug in Knuth's long division (TAOCP Vol II, Algorithm 4.3.1D)
Summary
A technical blog post recounts discovering a decades-old bug in Knuth's Algorithm D for long division, explores the mathematical underpinnings of long division, and discusses the interplay between theory and implementation, including an LLVM bug and a 2026 errata. It situates the discussion within historical division algorithms and practical implications for software libraries and cryptographic arithmetic.