Do not use -Og for debug mode (won't work on Mac/clang)

Author: axic

cmake/EthCompilerSettings.cmake

@@ -71,7 +71,7 @@ if (("${CMAKE_CXX_COMPILER_ID}" MATCHES "GNU") OR ("${CMAKE_CXX_COMPILER_ID}" MA
 	add_compile_options(-fPIC)
 
 	# Configuration-specific compiler settings.
-	set(CMAKE_CXX_FLAGS_DEBUG          "-Og -g -DETH_DEBUG")
+	set(CMAKE_CXX_FLAGS_DEBUG          "-O0 -g -DETH_DEBUG")
 	set(CMAKE_CXX_FLAGS_MINSIZEREL     "-Os -DNDEBUG")
 	set(CMAKE_CXX_FLAGS_RELEASE        "-O3 -DNDEBUG")
 	set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "-O2 -g")