[Feature Request]: consider using more accurate algorithm for sum() of floating-point values #1281

Python 3.16.0a0 (heads/main:ee68f5f46a1, Aug 12 2026, 11:19:39) [GCC 14.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> xs = [1.0,1e200,1.0,-1e200]
>>> sum(xs)
2.0
>>> res = xs[0]
... for t in xs[1:]:
...     res += t
... res  # naive result
... 
0.0

Python 3.13.14 (Thu Sep 17 18:51:21 UTC 2026)
[Graal, Oracle GraalVM, Java 25.0.4.1.1 (amd64)] on 'linux'
Type "help", "copyright", "credits" or "license" for more information.
>>> sum([1.0,1e200,1.0,-1e200])
0.0