$wasdiff-- if $wasdiff;
$wasdiff=3 if /^diff -/;
# Do not substitute already existing "./"... or "/dev/null".
- s{^\Q---\E (?![.]?/)}{$&./} if $wasdiff==2;
- s{^\Q+++\E (?![.]?/)}{$&./} if $wasdiff==1;
+ s{^(\Q---\E )(?:gdb-[^/]*/|[.]/)?}{$1./} if $wasdiff==2;
+ s{^(\Q+++\E )(?:gdb-[^/]*/|[.]/)?}{$1./} if $wasdiff==1;
next if /^[?]/;
next if /^Index:/;
next if /^={67}$/;