time builtin: incorrect formatting (e.g. 0m28.:00s)

Configuration Information [Automatically generated, do not change]:
Machine: x86_64
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS: -march=x86-64 -mtune=generic -O2 -pipe -fno-plt -fexceptions         -Wp,-D_FORTIFY_SOURCE=3 -Wformat -Werror=format-security         -fstack-clash-protection -fcf-protection         -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -g -ffile-prefix-map=/build/bash/src=/usr/src/debug/bash -flto=auto -DDEFAULT_PATH_VALUE='/usr/local/sbin:/usr/local/bin:/usr/bin' -DSTANDARD_UTILS_PATH='/usr/bin' -DSYS_BASHRC='/etc/bash.bashrc' -DSYS_BASH_LOGOUT='/etc/bash.bash_logout' -DNON_INTERACTIVE_LOGIN_SHELLS -std=gnu17
uname output: Linux tesla 6.18.2-arch2-1 #1 SMP PREEMPT_DYNAMIC Thu, 18 Dec 2025 18:00:18 +0000 x86_64 GNU/Linux
Machine Type: x86_64-pc-linux-gnu

Bash Version: 5.3
Patch Level: 9
Release Status: release

Description:
 	When running the built-in time command in bash, I got the
 	following output:

 	real    0m5.215s
 	user    0m28.:00s
 	sys     0m0.961s

 	The colon symbol in `0m28.:00s' seems out of place. It might be
 	some kind of an overflow error because ':' == '9' + 1. I have
 	tried investigating a bit and this line seems quite suspicious:

 	https://cgit.git.savannah.gnu.org/cgit/bash.git/tree/execute_cmd.c?h=devel#n1358

Repeat-By:
 	On my (slow) machine, the problem can be repeated by running:

 	$ time sleep .996

 	Most of the time, the result is:

 	real    0m0.:00s
 	user    0m0.000s
 	sys     0m0.004s

 	Running it on a different machine might need some adjustment of
 	the sleep amount.