Re: [CRIS] dwarf2 frame sniffer problem?

Orjan Friberg
2004-03-11T15:55:40Z

I don't know if this is related to the previous suggested problem (i.e.
the dwarf2 information being wrong), but I changed the test program
slightly to:

void bar(void) {}
void foo(void)
{
bar();
}
int main ()
{
foo();
return 0;
}

Now foo is no longer a leaf function, and thus saves the return address
on the stack in its prologue. Stepping over foo ("next" in main) causes
a breakpoint to be set at the first instruction in foo. After the
target is stopped at that instruction (which is where the return address
is pushed on the stack) dwarf2_frame_prev_register is called, which
thinks that the PC is saved on the stack (case
DWARF2_FRAME_REG_SAVED_OFFSET) and reads it from there. Obviously the
value it reads is wrong, since the return address hasn't been pushed yet.

What's wrong here? Is the dwarf2 debug information wrong, or should
dwarf2_frame_prev_register not have been called while still in the prologue?