Index: head/math/flann/Makefile
===================================================================
--- head/math/flann/Makefile	(revision 547859)
+++ head/math/flann/Makefile	(revision 547860)
@@ -1,26 +1,26 @@
 # $FreeBSD$
 
 PORTNAME=	flann
 DISTVERSION=	1.9.1-29
 DISTVERSIONSUFFIX=	-g1d04523
 CATEGORIES=	math
 
 MAINTAINER=	yuri@FreeBSD.org
 COMMENT=	Library for fast nearest neighbor searches in high dimensional spaces
 
 LICENSE=	BSD3CLAUSE
 LICENSE_FILE=	${WRKSRC}/COPYING
 
 LIB_DEPENDS=	libhdf5.so:science/hdf5 \
 		liblz4.so:archivers/liblz4 \
 		libsz.so:science/szip
 
-USES=		cmake localbase:ldflags pkgconfig
+USES=		cmake compiler:c++11-lang localbase:ldflags pkgconfig
 USE_GITHUB=	yes
 GH_ACCOUNT=	mariusmuja
 USE_LDCONFIG=	yes
 
 CMAKE_OFF=	BUILD_PYTHON_BINDINGS BUILD_MATLAB_BINDINGS BUILD_EXAMPLES BUILD_TESTS BUILD_DOC \
 		USE_OPENMP # OpenMP search is broken in cmake: https://gitlab.kitware.com/cmake/cmake/issues/17474
 
 .include <bsd.port.mk>
Index: head/math/flann/files/patch-src_cpp_CMakeLists.txt
===================================================================
--- head/math/flann/files/patch-src_cpp_CMakeLists.txt	(revision 547859)
+++ head/math/flann/files/patch-src_cpp_CMakeLists.txt	(revision 547860)
@@ -1,16 +1,10 @@
 --- src/cpp/CMakeLists.txt.orig	2019-04-07 03:21:23 UTC
 +++ src/cpp/CMakeLists.txt
-@@ -25,11 +25,11 @@ if (BUILD_CUDA_LIB)
+@@ -25,6 +25,6 @@ if (BUILD_CUDA_LIB)
      else()
  	    set(CUDA_NVCC_FLAGS "${CUDA_NVCC_FLAGS};" )
      endif()
 -    cuda_add_library(flann_cuda_s STATIC ${CU_SOURCES})
 +    cuda_add_library(flann_cuda_s SHARED ${CU_SOURCES})
      set_property(TARGET flann_cuda_s PROPERTY COMPILE_DEFINITIONS FLANN_STATIC)
  endif()
- 
--if(CMAKE_SYSTEM_NAME STREQUAL "Linux" AND CMAKE_COMPILER_IS_GNUCC)
-+if(CMAKE_SYSTEM_NAME MATCHES "Linux|FreeBSD|DragonFly" AND CMAKE_COMPILER_IS_GNUCC)
-     add_library(flann_cpp SHARED "")
-     set_target_properties(flann_cpp PROPERTIES LINKER_LANGUAGE CXX)
-     target_link_libraries(flann_cpp -Wl,-whole-archive flann_cpp_s -Wl,-no-whole-archive)