Configure CUB/Thrust for C++17 by default (#2217)

cub/cmake/CubBuildTargetList.cmake

@@ -40,12 +40,12 @@ set(CUB_CPP_DIALECT_OPTIONS
 )
 
 define_property(TARGET PROPERTY _CUB_DIALECT
-  BRIEF_DOCS "A target's C++ dialect: 11, 14, or 17."
-  FULL_DOCS "A target's C++ dialect: 11, 14, or 17."
+  BRIEF_DOCS "A target's C++ dialect: 11, 14, 17 or 20."
+  FULL_DOCS "A target's C++ dialect: 11, 14, 17 or 20."
 )
 define_property(TARGET PROPERTY _CUB_PREFIX
-  BRIEF_DOCS "A prefix describing the config, eg. 'cub.cpp14'."
-  FULL_DOCS "A prefix describing the config, eg. 'cub.cpp14'."
+  BRIEF_DOCS "A prefix describing the config, eg. 'cub.cpp17'."
+  FULL_DOCS "A prefix describing the config, eg. 'cub.cpp17'."
 )
 
 function(cub_set_target_properties target_name dialect prefix)
@@ -134,7 +134,7 @@ function(cub_build_target_list)
   foreach (dialect IN LISTS CUB_CPP_DIALECT_OPTIONS)
     # Create CMake options:
     set(default_value OFF)
-    if (dialect EQUAL 14) # Default to just 14 on:
+    if (dialect EQUAL 17) # Default to just 17 on:
       set(default_value ON)
     endif()
     option(CUB_ENABLE_DIALECT_CPP${dialect}

thrust/cmake/ThrustMultiConfig.cmake

@@ -15,7 +15,7 @@ function(thrust_configure_multiconfig)
     # Handle dialect options:
     foreach (dialect IN LISTS THRUST_CPP_DIALECT_OPTIONS)
       set(default_value OFF)
-      if (dialect EQUAL 14) # Default to just 14 on:
+      if (dialect EQUAL 17) # Default to just 17 on:
         set(default_value ON)
       endif()
       option(THRUST_MULTICONFIG_ENABLE_DIALECT_CPP${dialect}
@@ -112,7 +112,7 @@ function(thrust_configure_multiconfig)
       set_property(CACHE THRUST_DEVICE_SYSTEM PROPERTY TYPE STRING)
     endif()
 
-    set(THRUST_CPP_DIALECT 14
+    set(THRUST_CPP_DIALECT 17
       CACHE STRING "The C++ standard to target: ${THRUST_CPP_DIALECT_OPTIONS}"
     )
     set_property(CACHE THRUST_CPP_DIALECT