diff --git a/cmake/FindCUDA_wrap.cmake b/cmake/FindCUDA_wrap.cmake
index 40275bba9..d2de422a0 100755
--- a/cmake/FindCUDA_wrap.cmake
+++ b/cmake/FindCUDA_wrap.cmake
@@ -112,8 +112,9 @@ endif ()
 
 # 14-5-2016 PAOLO: WORKAROUND GCC 6.1 AND CUDA 7.5 INCOMPATIBILITY
 if (CMAKE_COMPILER_IS_GNUCC
-      AND (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 6.0))
-    set (CUDA_CXX_FLAGS "${CUDA_CXX_FLAGS},-std=c++98")
+    AND (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 6.0)
+    AND (NOT CUDA_VERSION_MAJOR VERSION_GREATER 7))
+  set (CUDA_CXX_FLAGS "${CUDA_CXX_FLAGS},-std=c++98")
 endif ()
 
 # ITK headers cannot be processed by nvcc, so we define
@@ -181,19 +182,25 @@ if (CUDA_FOUND)
       --Wno-deprecated-gpu-targets)
   endif ()
 
-  if (CUDA_VERSION_MAJOR EQUAL "9"
-      AND CMAKE_COMPILER_IS_GNUCC
-      AND NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 7.0)
-    list (APPEND CUDA_NVCC_FLAGS
-      --compiler-options -D__GNUC__=6)
-  endif ()
-  
-  # GCS 2017-10-24: Let CUDA work with gcc 6 and CUDA 8
+  # Let CUDA work with unsupported (too new) gcc versions
+  # Note: CUDA 10 cannot be used with gcc 10 or greater.
   if (CUDA_VERSION_MAJOR EQUAL "8"
       AND CMAKE_COMPILER_IS_GNUCC
       AND NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 6.0)
     list (APPEND CUDA_NVCC_FLAGS
       --compiler-options -D__GNUC__=5)
+  elseif (CUDA_VERSION_MAJOR EQUAL "9"
+      AND CMAKE_COMPILER_IS_GNUCC
+      AND NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 7.0)
+    list (APPEND CUDA_NVCC_FLAGS
+      --compiler-options -D__GNUC__=6)
+  elseif (CUDA_VERSION_MAJOR EQUAL "10"
+      AND CMAKE_COMPILER_IS_GNUCC)
+    if (NOT CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 9.0)
+      list (APPEND CUDA_NVCC_FLAGS
+	--compiler-options -D__GNUC__=8)
+      # For gcc 10, let it fail.
+    endif()
   endif ()
 
   # Choose compute capabilities
diff --git a/libs/ransac/RANSAC.h b/libs/ransac/RANSAC.h
index 15667488e..c454bc5d0 100644
--- a/libs/ransac/RANSAC.h
+++ b/libs/ransac/RANSAC.h
@@ -145,8 +145,13 @@ class RANSAC : public Object {
 	    return false;			
 	}
     };
-                   
-    static ITK_THREAD_RETURN_TYPE RANSACThreadCallback( void *arg );
+    static 
+#if ITK_VERSION_MAJOR >= 5
+    ITK_THREAD_RETURN_FUNCTION_CALL_CONVENTION
+#else
+    ITK_THREAD_RETURN_TYPE
+#endif
+        RANSACThreadCallback( void *arg );
 
     //number of threads used in computing the RANSAC hypotheses
     unsigned int numberOfThreads;
diff --git a/libs/ransac/RANSAC.txx b/libs/ransac/RANSAC.txx
index b0f628e4b..1149ce61c 100644
--- a/libs/ransac/RANSAC.txx
+++ b/libs/ransac/RANSAC.txx
@@ -150,7 +150,7 @@ double RANSAC<T,S>::Compute( std::vector<S> &parameters,
 
 template<class T, class S>
 #if ITK_VERSION_MAJOR >= 5
-itk::ITK_THREAD_RETURN_TYPE
+ITK_THREAD_RETURN_FUNCTION_CALL_CONVENTION
 #else
 ITK_THREAD_RETURN_TYPE
 #endif
diff --git a/src/plastimatch/base/direction_cosines.h b/src/plastimatch/base/direction_cosines.h
index 11f61eda4..26af47024 100644
--- a/src/plastimatch/base/direction_cosines.h
+++ b/src/plastimatch/base/direction_cosines.h
@@ -8,7 +8,9 @@
 #include <string>
 #include <stdio.h>
 
-#include "itk_image.h"
+#ifndef PLM_CUDA_COMPILE
+#include "itk_direction_type.h"
+#endif
 #include "plm_math.h"
 
 #define DIRECTION_COSINES_IDENTITY_THRESH 1e-9
@@ -25,7 +27,9 @@ class PLMBASE_API Direction_cosines {
 public:
     Direction_cosines ();
     Direction_cosines (const float *dm);
+#ifndef PLM_CUDA_COMPILE
     Direction_cosines (const DirectionType& itk_dc);
+#endif
     ~Direction_cosines ();
 
 public:
@@ -45,7 +49,9 @@ class PLMBASE_API Direction_cosines {
     float* get_matrix ();
     const float* get_inverse () const;
     void set (const float dc[]);
+#ifndef PLM_CUDA_COMPILE
     void set (const DirectionType& itk_dc);
+#endif
     bool set_from_string (std::string& str);
     bool is_identity ();
     std::string get_string () const;
diff --git a/src/plastimatch/base/itk_direction_type.h b/src/plastimatch/base/itk_direction_type.h
new file mode 100644
index 000000000..a60bee266
--- /dev/null
+++ b/src/plastimatch/base/itk_direction_type.h
@@ -0,0 +1,11 @@
+/* -----------------------------------------------------------------------
+   See COPYRIGHT.TXT and LICENSE.TXT for copyright and license information
+   ----------------------------------------------------------------------- */
+#ifndef _itk_direction_type_h_
+#define _itk_direction_type_h_
+
+#include "itkMatrix.h"
+
+typedef itk::Matrix < double, 3, 3 > DirectionType;
+
+#endif
diff --git a/src/plastimatch/base/itk_image.h b/src/plastimatch/base/itk_image.h
index 2c633948f..51f55c001 100644
--- a/src/plastimatch/base/itk_image.h
+++ b/src/plastimatch/base/itk_image.h
@@ -7,13 +7,13 @@
 #include "plmbase_config.h"
 #include "plm_int.h"
 
+#include "itk_direction_type.h"
 #include "itk_image_type.h"
 
 class Plm_image_header;
 class Volume_header;
 
 /* Other types */
-typedef itk::Matrix < double, 3, 3 > DirectionType;
 typedef itk::Index < 3 >  IndexType;
 typedef itk::Point < double, 3 >  OriginType;
 typedef itk::ImageRegion < 3 > RegionType;
diff --git a/src/plastimatch/register/registration.cxx b/src/plastimatch/register/registration.cxx
index dcc956056..0e40db7d9 100644
--- a/src/plastimatch/register/registration.cxx
+++ b/src/plastimatch/register/registration.cxx
@@ -587,7 +587,7 @@ Registration::run_main_thread ()
 
 static 
 #if ITK_VERSION_MAJOR >= 5
-itk::ITK_THREAD_RETURN_TYPE
+ITK_THREAD_RETURN_FUNCTION_CALL_CONVENTION
 #else
 ITK_THREAD_RETURN_TYPE
 #endif