Android: Add support for NDK r18

NDK r18 drops GCC toolchains and some STL types.  We need to choose a
clang toolchain by default when no gcc toolchains are available.  Switch
the STL type default to `c++_static` when the old `gnustl_static`
default is not available.

Update the test suite to not run tests for STL types that do not exist.
Also do not expect the gcc toolchain `cpp` tool to be available because
r18 does not provide it.  Also teach it to tolerate `gcc -dumpmachine`
output like `arm--linux-android` that differs from the toolchain prefix.

Fixes: #18301

2 files changed, 12 insertions, 6 deletions

diff --git a/Tests/RunCMake/Android/RunCMakeTest.cmake b/Tests/RunCMake/Android/RunCMakeTest.cmake
index 2027c4f..45798ce 100644
--- a/Tests/RunCMake/Android/RunCMakeTest.cmake
+++ b/Tests/RunCMake/Android/RunCMakeTest.cmake
@@ -61,8 +61,12 @@ foreach(ndk IN LISTS TEST_ANDROID_NDK)
       list(APPEND _abis_${_version} ${_abis})
     endif()
   endforeach()
-  set(_abis_ ${_abis_${_latest_gcc}})
   set(_abis_clang ${_abis_${_latest_clang}})
+  if(_latest_gcc)
+    set(_abis_ ${_abis_${_latest_gcc}})
+  else()
+    set(_abis_ ${_abis_clang})
+  endif()
   if(_versions MATCHES "clang")
     set(_versions "clang" ${_versions})
   endif()
@@ -132,10 +136,11 @@ foreach(ndk IN LISTS TEST_ANDROID_NDK)
   set(stl_types
     none
     system
-    gnustl_static
-    gnustl_shared
     )
 
+  if(IS_DIRECTORY "${ndk}/sources/cxx-stl/gnu-libstdc++")
+    list(APPEND stl_types gnustl_static gnustl_shared)
+  endif()
   if(IS_DIRECTORY "${ndk}/sources/cxx-stl/gabi++/libs")
     list(APPEND stl_types gabi++_static gabi++_shared)
   endif()
diff --git a/Tests/RunCMake/Android/common.cmake b/Tests/RunCMake/Android/common.cmake
index f931be1..aaa7c89 100644
--- a/Tests/RunCMake/Android/common.cmake
+++ b/Tests/RunCMake/Android/common.cmake
@@ -8,7 +8,6 @@ endif()
 foreach(f
     "${CMAKE_C_ANDROID_TOOLCHAIN_PREFIX}gcc${CMAKE_C_ANDROID_TOOLCHAIN_SUFFIX}"
     "${CMAKE_CXX_ANDROID_TOOLCHAIN_PREFIX}g++${CMAKE_CXX_ANDROID_TOOLCHAIN_SUFFIX}"
-    "${CMAKE_CXX_ANDROID_TOOLCHAIN_PREFIX}cpp${CMAKE_CXX_ANDROID_TOOLCHAIN_SUFFIX}"
     "${CMAKE_CXX_ANDROID_TOOLCHAIN_PREFIX}ar${CMAKE_CXX_ANDROID_TOOLCHAIN_SUFFIX}"
     "${CMAKE_CXX_ANDROID_TOOLCHAIN_PREFIX}ld${CMAKE_CXX_ANDROID_TOOLCHAIN_SUFFIX}"
     )
@@ -61,10 +60,12 @@ execute_process(
 if(NOT _res EQUAL 0)
   message(SEND_ERROR "Failed to run 'gcc -dumpmachine':\n ${_res}")
 endif()
-if(NOT _out STREQUAL "${CMAKE_C_ANDROID_TOOLCHAIN_MACHINE}")
+string(REPLACE "--" "-" _out_check "${_out}")
+if(NOT _out_check STREQUAL "${CMAKE_C_ANDROID_TOOLCHAIN_MACHINE}"
+    AND NOT (_out STREQUAL "arm--linux-android" AND CMAKE_C_ANDROID_TOOLCHAIN_MACHINE STREQUAL "arm-linux-androideabi"))
   message(SEND_ERROR "'gcc -dumpmachine' produced:\n"
     " ${_out}\n"
-    "which is not equal to CMAKE_C_ANDROID_TOOLCHAIN_MACHINE:\n"
+    "which does not match CMAKE_C_ANDROID_TOOLCHAIN_MACHINE:\n"
     " ${CMAKE_C_ANDROID_TOOLCHAIN_MACHINE}"
     )
 endif()