Error when compiling in Cygwin: "cannot run /bin/sh ./config.sub"

Question

Premise, this is the first time I try to compile anything. I am using the Cygwin (64-bit) terminal on a Windows machine.

I am trying to compile some source files that came in a tarball.

I navigate to the directory where I unzipped the tarball, then enter

./configure

After a couple of seconds, the shell responds:

configure: error: cannot run /bin/sh ./config.sub

config.log does not help clarify the issue:

## ----------- ##
## Core tests. ##
## ----------- ##

configure:2156: error: cannot run /bin/sh ./config.sub

I tried a couple of things. First of all, both config.sub and /bin/sh are there.

$ ./config.sub --help
Usage: ./config.sub [OPTION] CPU-MFR-OPSYS or ALIAS
[snip]

$ ls -l /bin/sh
-rwxr-xr-x 2 foo bar 739859 Jan 27  2017 /bin/sh

Second, the tarball is old (this is a 2013 release and it is the latest available. I prefer not to go into the details about what the code actually is, but if necessary I will, and I'm glad to provide more code snippets). After discovering what config.sub is, I tried to download the latest versions of config.sub and config.guess from Git. However, nothing changed.

I also tried to run the Cygwin terminal as Administrator.

The problem is not about CRLF/LF line endings: Files are saved in Unix format

Does anyone have any idea what might be going on?