crasher with undo and data structures
Can't reproduce a trivial demo at the moment. But it looks like a scalar somehow gums up the glist ordering logic in g_editor.c.
I can crash by creating a scalar in the same canvas with some objects, deleting some of the objects, creating new objects, and then undo'ing until I get a segfault.
gdb says it's line 1056 of g_editor.c:
y_prev->g_next = y;
So probably scalars are screwing up some reordering, leading to us de-referencing the next gobj when we're somehow already at the end of the glist...