Despite of the flawless execution of the configure-script, the current
development code does compile only after updating libassuan to the current
version 2.3.0

Although I do not know much about all this, I remember to have been alerted by
the configure scipt, when such a version clash had been detected.

The error code in the previously failing compile attempt had been :
gnupg/dirmngr/http.c:1478: undefined reference to `assuan_sock_get_flag'

But anyway, with the new library, all compiles alright.

Thanks for all.