Error with depth-only FBO on AMD GPUs

[eikel]

Initially reported by @eikel as #674:

Using an FBO without color texture triggers an error when calling glClear(GL_DEPTH_BUFFER_BIT);. There is no problem on NVIDIA GPUs so far. SVS's preprocessing uses such an FBO:

#0  Rendering::RenderingContext::clearDepth (this=0xa04c7c4, clearValue=1) at PADrend/src/Rendering/RenderingContext/RenderingContext.cpp:845
#1  0x03f6b4b5 in MinSG::VisibilitySubdivision::CostEvaluator::measure (this=0x28e530, context=..., node=...) at PADrend/src/MinSG/Ext/VisibilitySubdivision/CostEvaluator.cpp:65
#2  0x03f421c5 in MinSG::SphericalSampling::evaluateSample (sample=..., sphere=..., camera=0xfd6bc70, frameContext=..., evaluator=..., node=0xfd6c090) at PADrend/src/MinSG/Ext/SphericalSampling/SamplingSphere.cpp:108
#3  0x03f42361 in MinSG::SphericalSampling::SamplingSphere::evaluateAllSamples (this=0x28e450, frameContext=..., evaluator=..., camera=0xfd6bc70, node=0xfd6c090) at PADrend/src/MinSG/Ext/SphericalSampling/SamplingSphere.cpp:125
#4  0x03f3b234 in MinSG::SphericalSampling::createSamplingSphere (preprocessingContext=..., node=0xfd6c090) at PADrend/src/MinSG/Ext/SphericalSampling/Helper.cpp:332
#5  0x03f3a00f in MinSG::SphericalSampling::preprocessNode (preprocessingContext=..., node=0xfd6c090) at PADrend/src/MinSG/Ext/SphericalSampling/Helper.cpp:209
#6  0x03f3d9f3 in MinSG::SphericalSampling::PreprocessingContext::preprocessSingleNode (this=0xfe0b6ac) at PADrend/src/MinSG/Ext/SphericalSampling/PreprocessingContext.cpp:140
#7  0x01609f95 in E_MinSG::SphericalSampling::E_PreprocessingContext::_fnWrapper::function (runtime=..., caller=..., parameter=...) at PADrend/src/E_MinSG/Ext/SphericalSampling/E_PreprocessingContext.cpp:57
#8  0x6d7f7160 in EScript::RuntimeInternals::startFunctionExecution (this=0x9b000c8, fun=..., _callingObject=..., pValues=...) at PADrend/EScript/EScript/Runtime/RuntimeInternals.cpp:683
#9  0x6d7f42ec in EScript::RuntimeInternals::executeFunctionCallContext (this=0x9b000c8, fcc=...) at PADrend/EScript/EScript/Runtime/RuntimeInternals.cpp:184
#10 0x6d7f257d in EScript::Runtime::executeFunction (this=0x9b00030, fun=..., caller=..., _params=...) at PADrend/EScript/EScript/Runtime/Runtime.cpp:197
#11 0x69052e31 in _fu192___ZN3GUI6Window21ACTION_onWindowClosedE () at PADrend/src/E_GUI/E_GUI_Manager.cpp:419
#12 0x00c28231 in GUI::GUI_Manager::componentActionPerformed (this=0x9f7c0e0, c=0xfe0d428, actionName=...) at PADrend/src/GUI/GUI_Manager.cpp:663
#13 0x00bf8ca7 in GUI::Button::action (this=0xfe0d428) at PADrend/src/GUI/Components/Button.cpp:164
#14 0x00bf8b54 in GUI::Button::onMouseClick (this=0xfe0d428) at PADrend/src/GUI/Components/Button.cpp:126
#15 0x00c2743b in GUI::GUI_Manager::handleMouseButton (this=0x9f7c0e0, buttonEvent=...) at PADrend/src/GUI/GUI_Manager.cpp:423
#16 0x00c277fe in GUI::GUI_Manager::handleEvent (this=0x9f7c0e0, e=...) at PADrend/src/GUI/GUI_Manager.cpp:474
#17 0x69054145 in E_GUI::E_GUI_Manager::handleEvent (this=0x9f7c078, event=...) at PADrend/src/E_GUI/E_GUI_Manager.cpp:548
#18 0x69050895 in E_GUI::E_GUI_Manager::_fnWrapper::function (runtime=..., caller=..., parameter=...) at PADrend/src/E_GUI/E_GUI_Manager.cpp:254
#19 0x6d7f7160 in EScript::RuntimeInternals::startFunctionExecution (this=0x9b000c8, fun=..., _callingObject=..., pValues=...) at PADrend/EScript/EScript/Runtime/RuntimeInternals.cpp:683
#20 0x6d7f42ec in EScript::RuntimeInternals::executeFunctionCallContext (this=0x9b000c8, fcc=...) at PADrend/EScript/EScript/Runtime/RuntimeInternals.cpp:184
#21 0x6d7f257d in EScript::Runtime::executeFunction (this=0x9b00030, fun=..., caller=..., _params=...) at PADrend/EScript/EScript/Runtime/Runtime.cpp:197
#22 0x6d7fbdc2 in EScript::_eval (runtime=..., code=...) at PADrend/EScript/EScript/Utils/RuntimeHelper.cpp:80
#23 0x6d7fbe85 in EScript::_loadAndExecute (runtime=..., filename=...) at PADrend/EScript/EScript/Utils/RuntimeHelper.cpp:87
#24 0x6d8041ad in EScript::StdLib::_fnWrapper::function (rt=..., thisEObj=..., parameter=...) at PADrend/EScript/E_Libs/StdLib.cpp:241
#25 0x6d7f7160 in EScript::RuntimeInternals::startFunctionExecution (this=0x9b000c8, fun=..., _callingObject=..., pValues=...) at PADrend/EScript/EScript/Runtime/RuntimeInternals.cpp:683
#26 0x6d7f42ec in EScript::RuntimeInternals::executeFunctionCallContext (this=0x9b000c8, fcc=...) at PADrend/EScript/EScript/Runtime/RuntimeInternals.cpp:184
#27 0x6d7f257d in EScript::Runtime::executeFunction (this=0x9b00030, fun=..., caller=..., _params=...) at PADrend/EScript/EScript/Runtime/Runtime.cpp:197
#28 0x6d7fbdc2 in EScript::_eval (runtime=..., code=...) at PADrend/EScript/EScript/Utils/RuntimeHelper.cpp:80
#29 0x6d7fbe85 in EScript::_loadAndExecute (runtime=..., filename=...) at PADrend/EScript/EScript/Utils/RuntimeHelper.cpp:87
#30 0x6d7fbef2 in EScript::loadAndExecute (runtime=..., filename=...) at PADrend/EScript/EScript/Utils/RuntimeHelper.cpp:93
#31 0x004017c1 in main (argc=1, argv=0x6c8278) at PADrend/src/PADrend/main.cpp:137