--- Makefile	(revision 469304)
+++ Makefile	(working copy)
@@ -10,7 +10,7 @@ 
 DIST_SUBDIR=	arpack
 EXTRACT_ONLY=	${PORTNAME}${PORTVERSION}.tar.gz
 
-MAINTAINER=	ports@FreeBSD.org
+MAINTAINER=	robert.ayrapetyan@gmail.com
 COMMENT=	Argand Library: large eigenvalue subroutines (serial version)
 
 BUILD_DEPENDS=	tradcpp:devel/tradcpp
@@ -17,10 +17,8 @@ 
 
 CONFLICTS=	arpack-ng-[0-9]*
 CPP=		tradcpp
-FFLAGS+=	-ffixed-line-length-none
 LDFLAGS+=	-L${LOCALBASE}/lib
 MAKE_JOBS_UNSAFE=	yes
-USES=		fortran
 USE_LDCONFIG=	yes
 WRKSRC=		${WRKDIR}/ARPACK
 
@@ -67,10 +65,25 @@ 
 SYMTESTS=	ssdrv1 ssdrv2 ssdrv3 ssdrv4 ssdrv5 ssdrv6 \
 		dsdrv1 dsdrv2 dsdrv3 dsdrv4 dsdrv5 dsdrv6
 
-OPTIONS_DEFINE=	DOCS
+OPTIONS_DEFINE=       DOCS FLANG
 
+NO_FLANG_ARCHS=       i386 aarch64 armv6 armv7
+.for arch in ${NO_FLANG_ARCHS}
+    OPTIONS_EXCLUDE_${arch}=FLANG
+.endfor
+
+FLANG_DESC=           Use experimental flang instead of default Fortran compiler
+FLANG_USES=           fortran:flang
+FLANG_USES_OFF=       fortran
+
 .include <bsd.port.pre.mk>
 
+.if ${PORT_OPTIONS:MFLANG}
+    FFLAGS+=        -Mextend
+.else
+    FFLAGS+=        -ffixed-line-length-none
+.endif
+
 .if ${PORT_OPTIONS:MDOCS}
 DISTFILES+=	ug.ps.gz
 .endif