Server Mode: CMake process crashes when running into INTERFACE_LIBRARY targets

In a complex project the cmake server crashes with

cmake: /home/janickm/.local/pkg/cmake/Source/cmGeneratorTarget.cxx:954: void cmGeneratorTarget::GetSourceFiles(std::vector<std::__cxx11::basic_string<char> >&, const string&) const: Assertion `this->GetType() != cmState::INTERFACE_LIBRARY' failed.

using

$ cmake --version
cmake version 3.7.1

for the codemodel message type.

The project makes heavy use of interface libraries, but works fine in non-server mode.

---

The following commands are used

$ cmake -E server --experimental --debug

[== "CMake Server" ==[
{
    "buildDirectory": "/home/../<cmake-project>/build",
    "cookie": "",
    "generator": "Ninja",
    "major": 1,
    "protocolVersion": {
        "major": 1
    },
    "sourceDirectory": "/home/../<cmake-project>",
    "type": "handshake"
}
]== "CMake Server" ==]

[== "CMake Server" ==[
{
    "cacheArguments": [],
    "type": "configure"
}
]== "CMake Server" ==]

[== "CMake Server" ==[
{"type":"compute"}
]== "CMake Server" ==]

[== "CMake Server" ==[
{"type":"codemodel"}
]== "CMake Server" ==]

---

This was originally reported at https://bugreports.qt.io/browse/QTCREATORBUG-17496