Random lock in iOS

[d000hg]

I had my app running in the simulator while looking at something else, I noticed it had hung/crashed on a call to glDrawArrays() in OgreGLES2RenderSystem::_render() around line 1630:

Code: Select all

        else
        {
            do
            {
                // Update derived depth bias
                if (mDerivedDepthBias && mCurrentPassIterationNum > 0)
                {
                    _setDepthBias(mDerivedDepthBiasBase +
                                  mDerivedDepthBiasMultiplier * mCurrentPassIterationNum,
                                  mDerivedDepthBiasSlopeScale);
                }
                glDrawArrays((_getPolygonMode() == GL_FILL) ? primType : _getPolygonMode(), 0, op.vertexData->vertexCount);
                GL_CHECK_ERROR;
            } while (updatePassIterationRenderState());
        }

I seem able to step out of the GL methods (displayed as ASM) but no logging information is shown and I see this green "Thread 1: step over" line instead of a normal breakpoint. Once I'd stepped over a bit, I was even able to continue and the app started responding again.

And ideas what this means?

[d000hg]

This seems quite repeatable on the iOS simulator for me. I get that weird green 'thread breakpoint' after a couple of minutes not using the app, but I can continue in the debugger and it works again.

[masterfalcon]

No idea without some context. DrawArrays works fine here but maybe there's something particular about your situation. If you can boil it down to a simple reproduction case then perhaps we could see what's going on.

[d000hg]

I imagine that will be tricky

Can you tell me what that green breakpoint is - and since I can skip over it, can I turn it off completely? Also as I said I'm not seeing any log information, shouldn't GL_CHECK_ERROR be telling me something somewhere?

[masterfalcon]

If there's a GL error then yes it would help.

There isn't really a green breakpoint in Xcode. A green line indicates the current line being executed. If the debug information doesn't line up correctly with the source code(I've seen this happen a bunch, it's annoying) then you can get it hitting breaks where you haven't set a breakpoint.