diff --git a/astro/oskar/Makefile b/astro/oskar/Makefile
index c74d210139a9..7eefc5a645f0 100644
--- a/astro/oskar/Makefile
+++ b/astro/oskar/Makefile
@@ -12,6 +12,7 @@ LICENSE_FILE=	${WRKSRC}/LICENSE
 
 ONLY_FOR_ARCHS=		amd64 i386 powerpc powerpc64
 ONLY_FOR_ARCHS_REASON=	gccfeatures.h:54:4: This code has only been tested on x86 and powerpc platforms
+BROKEN_FreeBSD_12_powerpc64=	fails to compile: oskar_convert_cirs_relative_directions_to_enu_directions.c:67:29: 'csinl' undeclared (first use in this function)
 
 LIB_DEPENDS=	libcfitsio.so:astro/cfitsio