Merge pull request monero-project#994

79948db CMake: side-step Clang (CMake?) bug for Release build (anonimal)
ec33da0 CMake: set AppleClang detection and min version (anonimal)

CMakeLists.txt

@@ -120,6 +120,19 @@ elseif(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
     message(FATAL_ERROR "Clang 3.5 or higher is required")
   endif()
   set(CLANG TRUE)
+elseif(CMAKE_CXX_COMPILER_ID STREQUAL "AppleClang")
+  if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 8.0.0)
+    message(FATAL_ERROR "AppleClang 8.0.0 or higher is required")
+  endif()
+  set(CLANG TRUE)
+endif()
+
+# TODO(unassigned): an absolute hack to work around a clang (CMake?) bug that does not like our Release build type.
+#   Strangely, we don't do anything out of the ordinary with our Release build type, nor do our deps.
+#   The issue is not reproducible with Debug build type. See #993.
+#   Absolutely resolve this hack when are out of out Alpha, or no later than Beta.
+if (CLANG)
+  set(CMAKE_BUILD_TYPE Debug)
 endif()
 
 # Require C++14 support (minimum version compilers guarantee this)