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Left-shift of negative values is undefined [OSS-Fuzz issue 419059440]
OSS-Fuzz has found a bug in this project. Please see https://oss-fuzz.com/testcase?key=6323798310256640 for details and reproducers.
This issue is mirrored from https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=419059440 and will auto-close if the status changes there.
If you have trouble accessing this report, please file an issue at https://github.com/google/oss-fuzz/issues/new.
Left-shift of negative values is undefined. So, bitshift operations still need improvement.
Unfortunately, the jsonnet specification is lacking here. It just says:
Bitwise: Operators <<, >>, &, ^, | and ~ first convert their operands to signed 64 bit integers, then perform the operations in a standard way, then convert back to IEEE double precision floating point. In shift operations <<, >>, the right hand value modulo 64 is interpreted as the shift count. Shifting with a negative shift count raises an error.
But "then perform the operations in a standard way" is... highly ambiguous, since it doesn't indicate what standard might be followed here, and since some obvious choices of standards (eg, C++, at least prior to C++20) leave some of these behaviours incompletely defined.