DOC: added troubleshooting

README_SETUP.md

@@ -48,7 +48,7 @@ as compiler. We use [cmake](https://cmake.org/download/) as build tool.
    and build the project. (You can open Tools/Command Line/Developer Command
    Prompt and execute `msbuild libcaosdb.sln /property:Configuration=Release`)
 
-### Creating a Local Conan Build ##
+### Creating a Local Conan Package ##
 
 Building and installing libcaosdb with Conan is just a single command:  
 `conan create . -s "compiler.libcxx=libstdc++11"`
@@ -65,6 +65,10 @@ the `--build=missing` option: `conan install .. [ other options
 ] --build=missing`. This should download and compile the sources of the
 dependencies.
 
+#### cmake fails when using the Debug flag
+Depending on the clang version it might be necessary to use additionally the following flag:
+`-DCMAKE_CXX_FLAGS="-Wno-unused-parameter"`
+
 ## Unit Tests
 
 ### Build