Depends on how the GK was prevented from acting. In FIFA, the offense of "impeding the progress of an opponent" (as it is now called in FIFA, I think, although it's still "obstruction" in Fed) requires moving into an opponent's path; merely being in the way is not an offense.
https://www.fifa.com/mm/document/afd...t_en_47379.pdf, slide 29.
Of course, the penalty, an indirect kick, is the same for both offside and impeding.