"realpath" loadable (in the examples/loadables dir) infinite loops

[gazelle]

Configuration Information [Automatically generated, do not change]:
Machine: x86_64
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='x86_64' 
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='x86_64-unknown-linux-gnu' 
-DCONF_VENDOR='unknown' -DLOCALEDIR='/usr/local/share/locale' -DPACKAGE='bash' 
-DSHELL -DHAVE_CONFIG_H   -I.  -I. -I./include -I./lib   -g -O2 
-Wno-parentheses -Wno-format-security
uname output: Linux shell 4.4.0-79-generic #100-Ubuntu SMP Wed May 17 19:58:14 
UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
Machine Type: x86_64-unknown-linux-gnu

Bash Version: 4.4
Patch Level: 0
Release Status: release

Description:
        Command "realpath --help" causes infinite loop.

Repeat-By:
        enable -f /usr/local/lib/bash/realpath realpath
        realpath --help

        causes infinite loop of:

realpath: usage: realpath [-csv] pathname [pathname...]
realpath: usage: realpath [-csv] pathname [pathname...]
realpath: usage: realpath [-csv] pathname [pathname...]
realpath: usage: realpath [-csv] pathname [pathname...]
realpath: usage: realpath [-csv] pathname [pathname...]
realpath: usage: realpath [-csv] pathname [pathname...]

        until the shell is killed by signal 9 from another terminal.