Cannot connect to running QML debug server

sStarting debugger "QmlEngine" for ABI "x86-linux-generic-elf-64bit"...
dStart parameters: '' mode: 7
dABI: x86-linux-generic-elf-64bit
dLanguages: qml
dDebugger: /usr/bin/gdb
dProject: /home/ulf/dev/qtcreator-superAddtional Search Directories:
dQML server: 127.0.0.1:47428
dRemote: :0
dSysroot: 
dDebug Source Location: 
dDebugger settings: 
dUseCodeModel: true  (default: true)
dRaiseOnInterrupt: true  (default: true)
dStationaryEditorWhileStepping: false  (default: false)
dSwitchModeOnExit: false  (default: false)
dBreakpointsFullPath: false  (default: false)
dCloseBuffersOnExit: false  (default: false)
dCloseMemoryBuffersOnExit: true  (default: true)
dLogTimeStamps: false  (default: false)
dAutoQuit: false  (default: false)
dFontSizeFollowsEditor: false  (default: false)
dUseMessageBoxForSignals: true  (default: true)
dUseAlternatingRowColours: false  (default: false)
dQmlInspector.ShowAppOnTop: true  (default: false)  ***
dBreakOnAbort: false  (default: false)
dShowQmlObjectTree: true  (default: true)
dBreakOnWarning: false  (default: false)
dBreakOnFatal: false  (default: false)
dBreakOnThrow: false  (default: false)
dBreakOnCatch: false  (default: false)
dNoPluginBreakpoints: false  (default: false)
dSelectedPluginBreakpointsPattern: .*  (default: .*)
dSelectedPluginBreakpoints: false  (default: false)
dAdjustBreakpointLocations: true  (default: true)
dAllPluginBreakpoints: true  (default: true)
dSkipKnownFrames: false  (default: false)
dEnableReverseDebugging: false  (default: false)
dMaximalStringLength: 15000  (default: 10000)  ***
dDisplayStringLimit: 100  (default: 100)
dSortStructMembers: true  (default: true)
dAutoDerefPointers: false  (default: true)  ***
dShowQtNamespace: true  (default: true)
dShowQObjectNames: false  (default: false)
dShowStandardNamespace: true  (default: true)
dMaximalStackDepth: 20  (default: 20)
dIntelFlavor: false  (default: false)
dIdentifyDebugInfoPackages: false  (default: false)
dWarnOnReleaseBuilds: true  (default: true)
dMultiInferior: false  (default: false)
dUseDynamicType: true  (default: true)
dTargetAsync: false  (default: false)
dWatchdogTimeout: 20  (default: 20)
dAutoEnrichParameters: true  (default: true)
dGdbStartupCommands:   (default: )
dGdbPostAttachCommands:   (default: )
dLoadGdbDumpers2: false  (default: false)
dAttemptQuickStart: false  (default: false)
dIgnoreFirstChanceAccessViolation: false  (default: false)
dLoadGdbInit: true  (default: true)
dCDB_Console: false  (default: false)
dBreakpointCorrection: true  (default: true)
dBreakEvent:   (default: )
dBreakOnCrtDbgReport: false  (default: false)
dSymbolPaths:   (default: )
dSourcePaths:   (default: )
dGdbCustomDumperCommands:   (default: )
dAdditionalArguments:   (default: )
dAlwaysAdjustColumnWidths: true  (default: true)
dExtraDumperFile:   (default: )
dUseAddressInStackView: true  (default: false)  ***
dUseToolTipsInBreakpointsView: true  (default: true)
dUseAddressInBreakpointsView: false  (default: false)
dUseToolTipsInLocalsView: false  (default: false)
dUseToolTipsInBreakpointsView: true  (default: false)  ***
dShowThreadNames: true  (default: false)  ***
dUseToolTips: false  (default: true)  ***
dUseDebuggingHelper: true  (default: true)
dState changed from DebuggerNotReady(0) to EngineSetupRequested(1) [master]
dQUEUE: SETUP ENGINE
dCALL: SETUP ENGINE
dNOTE: ENGINE SETUP OK
dState changed from EngineSetupRequested(1) to EngineSetupOk(3) [master]
dQUEUE: SETUP INFERIOR
dState changed from EngineSetupOk(3) to InferiorSetupRequested(4) [master]
dQUEUE: SETUP INFERIOR
dCALL: SETUP INFERIOR
dNOTE: INFERIOR SETUP OK
dState changed from InferiorSetupRequested(4) to InferiorSetupOk(6) [master]
dState changed from InferiorSetupOk(6) to EngineRunRequested(7) [master]
dQUEUE: RUN ENGINE
dCALL: RUN ENGINE
sQML Debugger: Resolving host
sQML Debugger: Establishing network connection ...
sQML Debugger: Network connection dropped

dNOTE: ENGINE RUN FAILED
sRun failed.
dState changed from EngineRunRequested(7) to EngineRunFailed(8) [master]
dState changed from EngineRunFailed(8) to EngineShutdownRequested(19) [master]
dQUEUE: SHUTDOWN ENGINE
dQUIT DEBUGGER REQUESTED IN STATE 19
dCALL: SHUTDOWN ENGINE
dNOTE: ENGINE SHUTDOWN OK
dState changed from EngineShutdownRequested(19) to EngineShutdownOk(21) [master]
dState changed from EngineShutdownOk(21) to DebuggerFinished(22) [master]
dQUEUE: FINISH DEBUGGER
dNOTE: FINISH DEBUGGER
dHANDLE RUNCONTROL FINISHED
sDebugger finished.