autoconf 2.13 (probably applies to later versions too)

[Reuben Thomas]

On Cygwin, when running tests to find the sizeof various types, the test
programs write out a string of the form "%d\n", sizeof(foo), and then cat
the resulting file into a shell variable.

The problem is that the Cygwin cat always operates in binary mode, so if
the file is written on a partition mounted in text mode, then the
environment variable ends up getting a value which has a CR (^M) appended
to the end. This then confuses the configure script.

Removing the \n from the string seems to cure the problem.

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