I expect you need to install the "libnettle-devel" package to get headers for Nettle.
MSYS again
Marcus Comstedt (ACROSS) (Hail Ilpalazzo!) @ Pike (-) developers forum Wed, 22 Nov 2017 12:58:35 -0800
Marcus Comstedt (ACROSS) (Hail Ilpalazzo!) @ Pike (-) developers forum Wed, 22 Nov 2017 12:58:35 -0800
I expect you need to install the "libnettle-devel" package to get headers for Nettle.