Re: break instruction in mips32

[David Daney <ddaney@avtrex.com>]

Monika Chaddha wrote:
> Hi All
> 
> As per specification of mips32, 'break' instruction should raise the
> Breakpoint Exception but gdb6.0 does not raise any break point
> exception.
> 
> As my understanding in GDB, Breakpoint implementation is done with the
> help of break instruction. Whenever user puts any breakpoint the actual
> instruction at that point is replaced by break instruction and the
> actual instruction is maintained in other list.
> 
> If I use break instruction in user program it does not raise any
> exception. Does mips32 not support 'BREAK' instruction in GDB.
> 
> Thanks & Regards
> Monika
> 

I am not sure what problems you are having with break, but recent
official versions of binutils and linux kernel had some "issues" WRT
break and the mips32 target.  I don't know how these effect GDB.

The problem is that "break 7" should be converted to SIGFPE, and other
break codes should result in SIGTRAP.  The problem I mention causes the
break 7 to incorrectly SIGTRAP.

This may be of no help, but I thought I would mention it anyhow.

David Daney.