6 files changed, 26 insertions, 4 deletions
diff --git a/Help/manual/cmake-toolchains.7.rst b/Help/manual/cmake-toolchains.7.rst
index 74eab2d..64abe9a 100644
--- a/Help/manual/cmake-toolchains.7.rst
+++ b/Help/manual/cmake-toolchains.7.rst
@@ -387,7 +387,7 @@ Configure use of an Android NDK with the following variables:
 
 :variable:`CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION`
   Set to the version of the NDK toolchain to be selected as the compiler.
-  If not specified, the latest available GCC toolchain will be used.
+  If not specified, the default will be the latest available GCC toolchain.
 
 :variable:`CMAKE_ANDROID_STL_TYPE`
   Set to specify which C++ standard library to use.  If not specified,
diff --git a/Help/variable/CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION.rst b/Help/variable/CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION.rst
index dff7d64..5ae55d1 100644
--- a/Help/variable/CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION.rst
+++ b/Help/variable/CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION.rst
@@ -11,3 +11,6 @@ as the compiler.  The variable must be set to one of these forms:
 
 A toolchain of the requested version will be selected automatically to
 match the ABI named in the :variable:`CMAKE_ANDROID_ARCH_ABI` variable.
+
+If not specified, the default will be a value that selects the latest
+available GCC toolchain.
diff --git a/Modules/Platform/Android/Determine-Compiler-NDK.cmake b/Modules/Platform/Android/Determine-Compiler-NDK.cmake
index 953bc85..a33935b 100644
--- a/Modules/Platform/Android/Determine-Compiler-NDK.cmake
+++ b/Modules/Platform/Android/Determine-Compiler-NDK.cmake
@@ -52,6 +52,7 @@ unset(_ANDROID_CONFIG_MK_PATTERNS)
 # Find the newest toolchain version matching the ABI.
 set(_ANDROID_TOOL_NAME "")
 set(_ANDROID_TOOL_VERS 0)
+set(_ANDROID_TOOL_VERS_NDK "")
 set(_ANDROID_TOOL_SETUP_MK "")
 foreach(config_mk IN LISTS _ANDROID_CONFIG_MKS)
   # Check that the toolchain matches the ABI.
@@ -62,18 +63,21 @@ foreach(config_mk IN LISTS _ANDROID_CONFIG_MKS)
   unset(_ANDROID_TOOL_ABIS)
 
   # Check the version.
-  if("${config_mk}" MATCHES [[/([^/]+-(clang)?([0-9]\.[0-9]|))/config.mk$]])
+  if("${config_mk}" MATCHES [[/([^/]+-((clang)?([0-9]\.[0-9]|)))/config.mk$]])
     set(_ANDROID_CUR_NAME "${CMAKE_MATCH_1}")
-    set(_ANDROID_CUR_VERS "${CMAKE_MATCH_3}")
+    set(_ANDROID_CUR_VERS "${CMAKE_MATCH_4}")
+    set(_ANDROID_CUR_VERS_NDK "${CMAKE_MATCH_2}")
     if(_ANDROID_TOOL_VERS STREQUAL "")
       # already the latest possible
     elseif(_ANDROID_CUR_VERS STREQUAL "" OR _ANDROID_CUR_VERS VERSION_GREATER _ANDROID_TOOL_VERS)
       set(_ANDROID_TOOL_NAME "${_ANDROID_CUR_NAME}")
       set(_ANDROID_TOOL_VERS "${_ANDROID_CUR_VERS}")
+      set(_ANDROID_TOOL_VERS_NDK "${_ANDROID_CUR_VERS_NDK}")
       string(REPLACE "/config.mk" "/setup.mk" _ANDROID_TOOL_SETUP_MK "${config_mk}")
     endif()
     unset(_ANDROID_CUR_TOOL)
     unset(_ANDROID_CUR_VERS)
+    unset(_ANDROID_CUR_VERS_NDK)
   endif()
 endforeach()
 
@@ -206,6 +210,8 @@ endif()
 # Help CMakeFindBinUtils locate things.
 set(_CMAKE_TOOLCHAIN_PREFIX "${_ANDROID_TOOL_PREFIX}")
 
+set(_ANDROID_TOOL_NDK_TOOLCHAIN_VERSION "${_ANDROID_TOOL_VERS_NDK}")
+
 set(_ANDROID_TOOL_C_TOOLCHAIN_VERSION "${_ANDROID_TOOL_VERS}")
 set(_ANDROID_TOOL_C_TOOLCHAIN_PREFIX "${CMAKE_ANDROID_NDK}/toolchains/${_ANDROID_TOOL_NAME}/prebuilt/${_ANDROID_HOST_DIR}/bin/${_ANDROID_TOOL_PREFIX}")
 set(_ANDROID_TOOL_C_TOOLCHAIN_SUFFIX "${_ANDROID_HOST_EXT}")
@@ -231,6 +237,7 @@ endif()
 if(CMAKE_ANDROID_NDK_TOOLCHAIN_DEBUG)
   message(STATUS "_ANDROID_TOOL_NAME=${_ANDROID_TOOL_NAME}")
   message(STATUS "_ANDROID_TOOL_VERS=${_ANDROID_TOOL_VERS}")
+  message(STATUS "_ANDROID_TOOL_VERS_NDK=${_ANDROID_TOOL_VERS_NDK}")
   message(STATUS "_ANDROID_TOOL_PREFIX=${_ANDROID_TOOL_PREFIX}")
   message(STATUS "_ANDROID_TOOL_CLANG_NAME=${_ANDROID_TOOL_CLANG_NAME}")
   message(STATUS "_ANDROID_TOOL_CLANG_VERS=${_ANDROID_TOOL_CLANG_VERS}")
@@ -239,6 +246,7 @@ endif()
 
 unset(_ANDROID_TOOL_NAME)
 unset(_ANDROID_TOOL_VERS)
+unset(_ANDROID_TOOL_VERS_NDK)
 unset(_ANDROID_TOOL_PREFIX)
 unset(_ANDROID_TOOL_CLANG_NAME)
 unset(_ANDROID_TOOL_CLANG_VERS)
diff --git a/Modules/Platform/Android/Determine-Compiler-Standalone.cmake b/Modules/Platform/Android/Determine-Compiler-Standalone.cmake
index 6393105..9f07ab9 100644
--- a/Modules/Platform/Android/Determine-Compiler-Standalone.cmake
+++ b/Modules/Platform/Android/Determine-Compiler-Standalone.cmake
@@ -57,3 +57,5 @@ else()
   set(_ANDROID_TOOL_CXX_COMPILER "${_ANDROID_TOOL_CXX_TOOLCHAIN_PREFIX}g++${_ANDROID_TOOL_CXX_TOOLCHAIN_SUFFIX}")
   set(_ANDROID_TOOL_CXX_COMPILER_EXTERNAL_TOOLCHAIN "")
 endif()
+
+set(_ANDROID_TOOL_NDK_TOOLCHAIN_VERSION "")
diff --git a/Modules/Platform/Android/Determine-Compiler.cmake b/Modules/Platform/Android/Determine-Compiler.cmake
index 2fd2c4a..7ec703a 100644
--- a/Modules/Platform/Android/Determine-Compiler.cmake
+++ b/Modules/Platform/Android/Determine-Compiler.cmake
@@ -40,6 +40,7 @@ if(CMAKE_ANDROID_NDK)
 elseif(CMAKE_ANDROID_STANDALONE_TOOLCHAIN)
   include(Platform/Android/Determine-Compiler-Standalone)
 else()
+  set(_ANDROID_TOOL_NDK_TOOLCHAIN_VERSION "")
   set(_ANDROID_TOOL_C_COMPILER "")
   set(_ANDROID_TOOL_C_TOOLCHAIN_VERSION "")
   set(_ANDROID_TOOL_C_COMPILER_EXTERNAL_TOOLCHAIN "")
@@ -61,6 +62,7 @@ macro(__android_determine_compiler lang)
 
     # Save the Android-specific information in CMake${lang}Compiler.cmake.
     set(CMAKE_${lang}_COMPILER_CUSTOM_CODE "
+set(CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION \"${_ANDROID_TOOL_NDK_TOOLCHAIN_VERSION}\")
 set(CMAKE_${lang}_ANDROID_TOOLCHAIN_VERSION \"${_ANDROID_TOOL_${lang}_TOOLCHAIN_VERSION}\")
 set(CMAKE_${lang}_COMPILER_EXTERNAL_TOOLCHAIN \"${_ANDROID_TOOL_${lang}_COMPILER_EXTERNAL_TOOLCHAIN}\")
 set(CMAKE_${lang}_ANDROID_TOOLCHAIN_PREFIX \"${_ANDROID_TOOL_${lang}_TOOLCHAIN_PREFIX}\")
diff --git a/Tests/RunCMake/Android/common.cmake b/Tests/RunCMake/Android/common.cmake
index d803c98..18c9797 100644
--- a/Tests/RunCMake/Android/common.cmake
+++ b/Tests/RunCMake/Android/common.cmake
@@ -22,8 +22,15 @@ string(APPEND CMAKE_CXX_FLAGS " -Werror -Wno-attributes")
 string(APPEND CMAKE_EXE_LINKER_FLAGS " -Wl,-no-undefined")
 
 if(CMAKE_ANDROID_NDK)
-  if(CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION MATCHES "clang")
+  if(NOT CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION)
+    message(SEND_ERROR "CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION is not set!")
+  elseif(CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION MATCHES "^clang")
     add_definitions(-DCOMPILER_IS_CLANG)
+  elseif(NOT "${CMAKE_C_COMPILER}" MATCHES "toolchains/[^/]+-${CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION}/prebuilt")
+    message(SEND_ERROR "CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION is\n"
+      "  ${CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION}\n"
+      "which does not appear in CMAKE_C_COMPILER:\n"
+      "  ${CMAKE_C_COMPILER}")
   endif()
 elseif(CMAKE_ANDROID_STANDALONE_TOOLCHAIN)
   execute_process(