Add definition for 0 in case it's not available in cross.fs

: gxt-location ( addr -- addr )

\ note that an xt was compiled at addr, for backtrace-locate functionality

    dup glocs-start - T 1 cells H / >r

    tsourceview dup r> 1+ cross-locs[] $[] cell- 2! ;

    tsourceview dup r> 1+ cross-locs[] $[] 1 cells - 2! ;

\ search for ghosts