In the 2.1.0 framework version, the last argument of the glGetShaderSource was changed from StringBuilder to StringBuilder[]. While it is possible to pass an array consisting of a single StringBuilder to the function, the results are always null.
I'm assuming it's a typo in the source for the code generator. The prototypes of all other functions taking a StringBuilder remained unchanged.

Old prototype:
public static void glGetShaderSource(int shader, int bufSize, out int length, StringBuilder source);

New prototype:

public static void glGetShaderSource(int shader, int bufSize, out int length, StringBuilder[] source);

The meaning of bufSize in 2.1.0 was changed to mean the size of the StringBuilder[] array, not the maximum character capacity.

This is how it worked before:

int length;
var sb = new StringBuilder( 8192 );
Gl.glGetShaderSource( shader.Handle, sb.Capacity, out length, sb );
// sb contains shader source, length is correct


This is how I tried to use it in 2.1.0, without success:

int length;
var sb = new StringBuilder( 8192 );
var x = new StringBuilder[] { sb };
Gl.glGetShaderSource( shader.Handle, 1, out length, x );
// sb is empty, length is zero
// notice the 'capacity' parameter had to be changed to 1 to prevent the call from crashing


It's not really that important of a function, I only noticed this because it broke some of my code, so don't lose any sleep over it. And again, thanks for all your nice work.

Gregor.