Index: head/databases/xtrabackup/Makefile
===================================================================
--- head/databases/xtrabackup/Makefile	(revision 565267)
+++ head/databases/xtrabackup/Makefile	(revision 565268)
@@ -1,50 +1,62 @@
 # Created by: Alex Samorukov <samm@freebsd.org>
 # $FreeBSD$
 
 PORTNAME=	xtrabackup
 DISTVERSION=	2.4.21
 CATEGORIES=	databases
 MASTER_SITES=	https://www.percona.com/downloads/Percona-XtraBackup-${PORTVERSION:R}/Percona-XtraBackup-${PORTVERSION}/source/tarball/:xtrabackup \
 		https://ftp.osuosl.org/pub/blfs/conglomeration/boost/:boost SF/boost/boost/1.59.0/:boost
 DISTFILES=	percona-${PORTNAME}-${PORTVERSION}.tar.gz:xtrabackup \
 		boost_1_59_0.tar.bz2:boost
 
 MAINTAINER=	samm@FreeBSD.org
 COMMENT=	OpenSource version of InnoDB backup with support of Percona extensions
 
 LICENSE=	GPLv2
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
 BROKEN_armv6=		fails to compile: cannot combine with previous 'type-name' declaration specifier
 BROKEN_armv7=		fails to compile: cannot combine with previous 'type-name' declaration specifier
 BROKEN_mips64=		fails to compile: 'fpsetmask' was not declared in this scope
 
 # quilt is required by build.sh
 BUILD_DEPENDS=	bash:shells/bash \
 		cmake:devel/cmake
 LIB_DEPENDS=	libcurl.so:ftp/curl \
 		libev.so:devel/libev \
 		libgcrypt.so:security/libgcrypt \
 		libgpg-error.so:security/libgpg-error
 RUN_DEPENDS=	qpress:archivers/qpress
 
-CONFLICTS_INSTALL=	${PORTNAME}8
-
-# autotool is in use for 5.1 builds
 USES=		alias autoreconf:build bison cmake:noninja compiler:c++11-lang \
 		cpe gettext libtool perl5 shebangfix
 USE_CXXSTD=	c++11
+
+CONFLICTS_INSTALL=	${PORTNAME}8
+
 CPE_VENDOR=	percona
 SHEBANG_FILES=	storage/innobase/xtrabackup/xbcloud_osenv.sh
 CMAKE_ARGS=	-DWITH_BOOST=${WRKDIR}/boost_1_59_0 -DWITH_VERSION_CHECK=OFF
 
 WRKSRC=		${WRKDIR}/percona-${PORTNAME}-${PORTVERSION}
 
 PLIST_FILES=	bin/xtrabackup bin/xbstream bin/innobackupex bin/xbcrypt \
 		bin/xbcloud bin/xbcloud_osenv
 
+.include <bsd.port.pre.mk>
+# xtrabackup/mysql57 fails to compile with llvm11, which was imported to current in r364284
+# without a version increase (1300109 = r364274).
+# Until a proper fix is provided, simply use llvm from ports, which probably could be
+# a backport of amongst other tings:
+# https://github.com/mysql/mysql-server/commit/08f46b3c00ee70e7ed7825daeb91df2289f80f50
+.if ${CHOSEN_COMPILER_TYPE} == clang && ${OPSYS} == FreeBSD && ${OSVERSION} >= 1300109
+BUILD_DEPENDS+=	clang${LLVM_DEFAULT}:devel/llvm${LLVM_DEFAULT}
+CC=		${LOCALBASE}/bin/clang${LLVM_DEFAULT}
+CXX=		${LOCALBASE}/bin/clang++${LLVM_DEFAULT}
+.endif
+
 # Not sure why it's trying to install mysql client libraries now
 post-install:
 	${RM} -rf ${STAGEDIR}${LOCALBASE}/lib
 
-.include <bsd.port.mk>
+.include <bsd.port.post.mk>