diff --git a/math/libxsmm/Makefile b/math/libxsmm/Makefile
index 381aa4ab3fd5..25ece4924f12 100644
--- a/math/libxsmm/Makefile
+++ b/math/libxsmm/Makefile
@@ -1,38 +1,39 @@
 PORTNAME=	libxsmm
 DISTVERSION=	1.16.3
 CATEGORIES=	math science
 
 MAINTAINER=	yuri@FreeBSD.org
 COMMENT=	Library for dense and sparse matrix operations and deep learning
 
 LICENSE=	BSD3CLAUSE
 LICENSE_FILE=	${WRKSRC}/LICENSE.md
 
 BROKEN_i386=	error: assigning to '__m256i' (vector of 4 'long long' values) from incompatible type 'int'
+BROKEN_aarch64=	error: invalid output constraint '=a', see https://github.com/libxsmm/libxsmm/issues/669
 
 BUILD_DEPENDS=	bash:shells/bash
 
 USES=		cpe fortran gmake localbase:ldflags python:build shebangfix
 CPE_VENDOR=	${PORTNAME}_project
 SHEBANG_GLOB=	*.sh
 USE_GITHUB=	yes
 GH_ACCOUNT=	hfp
 USE_LDCONFIG=	yes
 
 MAKE_ARGS=	STATIC=0 DEPSTATIC=0 MAKE_PARALLEL=1
 LDFLAGS+=	-lm
 
 TEST_TARGET=	tests
 
 BINARY_ALIAS=	python=${PYTHON_CMD}
 
 .include <bsd.port.options.mk>
 
 .if ${ARCH} != amd64
 MAKE_ARGS+=	PLATFORM=1
 .endif
 
 post-install: # https://github.com/hfp/libxsmm/issues/413
 	${RMDIR} ${STAGEDIR}${PREFIX}/share/modules
 
 .include <bsd.port.mk>