std.fmt: Fix incorrect behavior with large floating point integers. #11380
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I consider this an interim workaround/hack until ziglang#1299 is finished. There is a bug in the original C implementation of the errol3 (and errol4) algorithm that can result in undefined behavior or an obviously incorrect result (leading ':' in the output) This change checks for those two problems and uses a slower fallback path if they occur. I can't guarantee that this will always produce the correct result, but since the workaround is only used if the original algorithm is guaranteed to fail, it should never turn a previously-correct result into an incorrect one. Fixes ziglang#11283
Vexu
approved these changes
Apr 4, 2022
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I consider this an interim workaround/hack until #1299 is finished.
There is a bug in the original C implementation of the errol3 (and errol4)
algorithm that can result in undefined behavior or an obviously incorrect
result (leading ':' in the output)
This change checks for those two problems and uses a slower fallback
path if they occur. I can't guarantee that this will always produce
the correct result, but since the workaround is only used if the original
algorithm is guaranteed to fail, it should never turn a previously-correct
result into an incorrect one.
Fixes #11283