Eli Zaretskii wrote:
> I see this both on GNU/Linux and on MS-Windows.

Ah, it worked for me under GNU/Linux with GCC 7.3.0 (Ubuntu 18.04) and with GCC 
8.2.1 20181105 (Red Hat 8.2.1-5) (Fedora 29). But I see now that the code was 
relying on a feature that C99 does not require, and perhaps you're using older 
GCCs. I installed the attached patch, which should port to C99; I hope it works 
for you.