Sorry to have taken sol long...
I've applied the patch because it does still pass the checks, but I've got a few remarks which, I'm sure you can correct quickly ;)
* once the is_freeable flag is set to FALSE, there is no way it can be back to TRUE
* the real_gda_holder_set_const_value() function seems to return NULL all the time (the inline doc is not helpfull)
* I'm not sure the copy function is correct because it both copies the is_freeable flag and the priv->value
I'll wait for your corrections before pushing
3.99.5.Thanks,
Vivien