fix(mpack): wrong encoding of integers beyond the int32 range #42085

Problem:
vim.mpack.encode() picks the msgpack size of a negative integer from its
low 32 bits only, so -(2^32 + 5) is written as a negative fixint and
decodes as -5. Numbers beyond +-2^53 trip an assertion in debug builds.
In release builds, numbers below -2^63 or from 2^64 up go through
out-of-range conversions: -1.5 * 2^63 decodes as 2^62.

Solution:
Use int64 whenever the high word is not a sign extension. Encode numbers
outside [-2^63, 2^64), including NaN and infinities, as floats.

AI-assisted

0 files changed, 0 insertions, 0 deletions