Problem OpenGLES Book iPhone 3D Programming

[Nos]

I bought the book iPhone 3D Programming by Philip Rideout to start learning OpenGLES but when i tried to reproduce the first example HelloArrow, the build failed :
Unknown type name 'virtual'
I downloaded the source for this example and when i tried to compile it, the build succeeded. Why ? I compared my source and the example's source, no differences.

I'm using XCode 4.2, the last build release. Why XCode 4.2 doesn't know the type 'virtual' ?

The type virtual is declared in IRenderingEngine.h :
struct IRenderingEngine {
virtual void Initialize(int width, int height) = 0;
virtual void Render() const = 0;
virtual void UpdateAnimation(float timeStep) = 0;
virtual void OnRotate(DeviceOrientation newOrientation) = 0;
virtual ~IRenderingEngine(){}
};

Has anyone try this example with XCode 4.2 ?

Best regards,

[Nos]

Sorry, i found the solution by myself :
you must rename all files .m in .mm (even main.m)

[cybohemia]

Originally Posted by Nos

you must rename all files .m in .mm (even main.m)

I'm having the same problem and tried re-naming the files to .m but that didn't fix the problem. The code is actually in a .hpp file, not a .mm file - was there anything else you had done that might have helped to fixed things?

Thanks.