bash hangs on cygwin-3.5.5-1

[Bruno Haible]

This is not reproducible, but here's the report anyway:

I upgraded a Windows 10 system from Cygwin 3.5.3 to 3.5.5 today.
Then ran the configure script of a tarball (*), and it hung:

$ mkdir build-cygwin64
$ cd build-cygwin64
$ ../configure --host=x86_64-pc-cygwin --prefix=/usr/local/cygwin64 CC=x86_64-pc-cygwin-gcc CXX=x86_64-pc-cygwin-g++ CPPFLAGS="-I/usr/local/cygwin64/include -Wall" LDFLAGS=-L/usr/local/cygwin64/lib -C --with-included-libunistring 2>&1 | tee log1
...
checking whether snprintf fully supports the 'n' directive... (cached) yes
checking whether snprintf respects a size of 1... (cached) yes
checking whether vsnprintf respects a zero size as in C99... (cached) yes
checking whether btowc is declared without a macro... yes
checking whether wctob is declared without a macro... yes
checking whether mbsinit is declared without a macro... yes
checking whether mbrtowc is declared without a macro... yes
<hangs>

Typing Ctrl-C in said mintty window has no effect.


(*) generated in a gnulib checkout on Linux, through
    $ ./gnulib-tool --create-testdir --dir=../testdir-all --with-c++-tests --without-privileged-tests --single-configure `./all-modules`