Unfortunately the suggested fix (replacing sync_fetch_and_add_4 by sync_fetch_and_add_N) breaks compatibility with previous versions of GNAT (as recent as GNAT CE 21).
I get (trying with both 'N' and 'n'):
gnatcom-initialize.adb:85:1: undefined reference to __sync_fetch_and_add_N
gnatcom-initialize.adb:85:1: undefined reference to __sync_fetch_and_add_n
Perhaps it is better to try disabling the warning.
The issue is the name used with the pragma Import on sync_fetch_and_add in gnatcom-initialize.adb, using a recent version of GNAT Pro. See:
https://sourceforge.net/p/gnavi/bugs/14/
Unfortunately the suggested fix (replacing sync_fetch_and_add_4 by sync_fetch_and_add_N) breaks compatibility with previous versions of GNAT (as recent as GNAT CE 21). I get (trying with both 'N' and 'n'): gnatcom-initialize.adb:85:1: undefined reference to
__sync_fetch_and_add_Ngnatcom-initialize.adb:85:1: undefined reference to__sync_fetch_and_add_nPerhaps it is better to try disabling the warning.