Cygwin bash build- command substitution fails

[Dave Taylor]

Configuration Information [Automatically generated, do not change]:
Machine: x86_64
OS: cygwin
Compiler: gcc
Compilation CFLAGS:  -DPROGRAM='bash.exe' -DCONF_HOSTTYPE='x86_64'
-DCONF_OSTYPE='cygwin' -DCONF_MACHTYPE='x86_64-unknown-cygwin'
-DCONF_VENDOR='unknown' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash'
-DSHELL -DHAVE_CONFIG_H -DRECYCLES_PIDS   -I.
 -I/usr/src/bash-4.4.12-3.x86_64/src/bash-4.4
-I/usr/src/bash-4.4.12-3.x86_64/src/bash-4.4/include
-I/usr/src/bash-4.4.12-3.x86_64/src/bash-4.4/lib  -DWORDEXP_OPTION -ggdb
-O2 -pipe -Wimplicit-function-declaration
-fdebug-prefix-map=/usr/src/bash-4.4.12-3.x86_64/build=/usr/src/debug/bash-4.4.12-3
-fdebug-prefix-map=/usr/src/bash-4.4.12-3.x86_64/src/bash-4.4=/usr/src/debug/bash-4.4.12-3
-Wno-parentheses -Wno-format-security
uname output: CYGWIN_NT-10.0 ddtlap 3.0.7(0.338/5/3) 2019-04-30 18:08
x86_64 Cygwin
Machine Type: x86_64-unknown-cygwin

Bash Version: 4.4
Patch Level: 12
Release Status: release

Description:
I'm trying to do a Cygwin build of the bash git repo at bminor/bash on
github.

The configure (no options) and make (no options) finish successfully, but
the build fails when doing $()-style command substitutions, claiming that
the trailing paren is unexpected:

% echo $(echo hiya)
bash: command substitution: line 9: syntax error near unexpected token `)'
bash: command substitution: line 9: `echo hiya)'
%

Note that other approaches to command substitution seem to work:

% echo $(echo hiya
> )
hiya
%

% echo `echo hiya`
hiya
%

Repeat-By:

Install cygwin (ver 3.1.0-1)
Install cygwin-devel (ver 3.1.0-1)
Install autoconf2.5 (ver 2.69-4)
Install autoconf (ver 13-1)
git clone https://github.com/bminor/bash.git
cd bash
./configure
make
./bash
echo $(echo hiya)