gcc info

[regis.fouret@free.fr]

hello there
i  ve heard it is preferable to compile kernel modules with the same
version of gcc than the one used to compile the kernel .
what are the exact reasons for this ?
i ve heard of bugs leading to incompatibility in the linking format between 
versions of gcc . is that true ?
if yes why would these bugs have survived considering this is a crucial point 
?

thanks in advance for any answer