Index: head/databases/galera/Makefile
===================================================================
--- head/databases/galera/Makefile	(revision 441685)
+++ head/databases/galera/Makefile	(revision 441686)
@@ -1,63 +1,74 @@
 # Created by: Horia Racoviceanu <horia@racoviceanu.com>
 # $FreeBSD$
 
 PORTNAME=	galera
 PORTVERSION=	25.3.20
 PORTREVISION=	2
 CATEGORIES=	databases
 
 MAINTAINER=	devel@galeracluster.com
 COMMENT=	Synchronous multi-master replication engine
 
 LICENSE=	GPLv2
 
 BUILD_DEPENDS=	checkmk:devel/check \
 		${LOCALBASE}/include/boost/shared_ptr.hpp:devel/boost-libs
 LIB_DEPENDS=	libboost_date_time.so:devel/boost-libs
 
+NOT_FOR_ARCHS=	i386
+# On i386 older versions of clang produce:
+#   cannot compile this atomic library call yet ... __atomic_add_fetch
+# whereas newer ones generate a call to __atomic_add_fetch which ends up with
+# undefined reference at link time:
+#   undefined reference to `__atomic_fetch_add_8'
+# https://bugs.llvm.org//show_bug.cgi?id=23262
+# https://bugs.llvm.org//show_bug.cgi?id=24908
+# https://tracker.crystax.net/issues/1263
+NOT_FOR_ARCHS_REASON_i386=Uses 64 bit atomics that clang cannot generate on i386
+
 USES=		execinfo python:build scons ssl
 
 USE_LDCONFIG=	yes
 
 USE_GITHUB=	yes
 GH_ACCOUNT=	codership
 GH_TAGNAME=	release_${DISTVERSION}
 
 LDFLAGS+=	-lboost_program_options -lboost_system
 MAKE_ARGS+=	--config=force \
 		deterministic_tests=1 \
 		revno=${GH_TAGNAME} \
 		system_asio=0
 
 USE_RC_SUBR=	garb.sh
 
 PLIST_FILES=	bin/garbd \
 		lib/libgalera.so \
 		lib/libgalera_smm.so
 
 OPTIONS_DEFINE=	BOOSTPOOL BPOSTATIC DEBUG
 
 BOOSTPOOL_DESC=	Use boost pool allocator
 BPOSTATIC_DESC=	Use static boost_program_options
 
 .include <bsd.port.pre.mk>
 
 .if ${PORT_OPTIONS:MBOOSTPOOL}
 MAKE_ARGS+=	boost_pool=1
 .endif
 
 .if ${PORT_OPTIONS:MBPOSTATIC}
 MAKE_ARGS+=	bpostatic=${LOCALBASE}/lib/libboost_program_options.a
 .endif
 
 .if ${PORT_OPTIONS:MDEBUG}
 MAKE_ARGS+=	debug=3
 .endif
 
 do-install:
 	${INSTALL_PROGRAM} ${WRKSRC}/garb/garbd ${STAGEDIR}${PREFIX}/bin/
 	${INSTALL_LIB} ${WRKSRC}/libgalera_smm.so ${STAGEDIR}${PREFIX}/lib/
 	@(cd ${STAGEDIR}${PREFIX}/lib && ${LN} -sf libgalera_smm.so \
 		libgalera.so)
 
 .include <bsd.port.post.mk>