The stack buffer displays a call stack, with one line for each of the nested subroutine calls (stack frames) now active in the program. See.
An arrow in the fringe points to the selected frame or, if the fringe is
not present, the number of the selected frame is displayed in reverse
contrast. To select a frame in GDB, move point in the stack buffer to
that stack frame and type <RET> (
gdb-frames-select), or click
Mouse-2 on a stack frame. If the locals buffer is visible,
selecting a stack frame updates it to display the local variables of the