printf sometimes doesn't round numbers to even

[dustwanderer]

Description / Steps to reproduce the issue

1- printf "%.1f %.1f" 76.75 76.85 = 76.8 76.8 # Round to nearest and ties to even.
2- printf "%.0f %.0f" 24.5 25.5 = 24 26 # Round to nearest and ties to even.
3- printf "%.1f %.1f" 2.45 2.55 = 2.5 2.5 # Whatever happened to ties to even?

Expected behavior

printf "%.1f %.1f" 2.45 2.55 should output "2.4 2.6". That would follow standard conventions and will be coherent with printf rounding of "24.5 25.5" to "24 26".

Actual behavior

printf "%.1f %.1f" 2.45 2.55 outputs "2.5 2.5".

Verification

• I have verified that my MSYS2 is up-to-date before submitting the report (see https://www.msys2.org/docs/updating/)

Windows Version

MSYS_NT-10.0-26200

Are you willing to submit a PR?

No response

[dragon-archer]

I think this is an upstream issue.

I've tested this on linux with almost latest bash (5.3.9), zsh (5.9) and coreutils (9.7) (all from Ubuntu 26.10), and they all (builtins of bash and zsh + /usr/bin/printf from coreutils) have the same issue.

Notice that printf from uutils 0.8.0 seemes to print correctly.

[oech3]

Should we report this to uutils as compability issue?

[lazka]

I think someone has to write a proper upstream bug report instead of linking here, otherwise it likely will be ignored.