fort uses stdatomic.h and needs to use either base-clang or ports-gcc.
With this diff fort compiles on sparc64

Does this require a bump?
-- 
:wq Claudio

Index: Makefile
===================================================================
RCS file: /cvs/ports/net/fort/Makefile,v
diff -u -p -r1.2 Makefile
--- Makefile	19 Jan 2024 14:26:09 -0000	1.2
+++ Makefile	13 Feb 2024 11:08:17 -0000
@@ -13,6 +13,9 @@ MAINTAINER =		Claudio Jeker <claudio@ope
 # MIT
 PERMIT_PACKAGE =	Yes
 
+# stdatomic.h
+COMPILER =		base-clang ports-gcc
+
 SITES =			https://github.com/NICMx/FORT-validator/releases/download/$V/
 CONFIGURE_STYLE =	gnu
 CONFIGURE_ENV +=	CPPFLAGS="-I${LOCALBASE}/include" \