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gdb/624: temporary breakpoint commands lists not executed


>Number:         624
>Category:       gdb
>Synopsis:       temporary breakpoint commands lists not executed
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Jul 31 12:38:01 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     Joel Brobecker
>Release:        unknown-1.0
>Organization:
>Environment:
Platform independent bug, reproduced on x86-linux.
GNU gdb 2002-07-27-cvs.
>Description:
Using the small program from gdb.base/commands.exp, the following copy
of a GDB sessions shows that commands associated to temporary
breakpoints are not executed when the breakpoint is hit:

        (gdb) tbreak factorial
        Breakpoint 1 at 0x8048582: file ./gdb.base/run.c, line 77.
        (gdb) commands
        Type commands for when breakpoint 1 is hit, one per line.
        End with a line saying just "end".
        >silent
        >printf "factorial command-list executed\n"
        >cont
        >end
        (gdb) run 1
        Starting program: [...]/gdb.base/commands 1
        (gdb)

The backtrace confirms that the program executed up to the factorial
breakpoint, and then stopped.

        (gdb) bt
        #0  factorial (value=1) at ./gdb.base/run.c:77
        #1  0x0804855e in main (argc=2, argv=0xbffffa34, envp=0xbffffa40)
            at ./gdb.base/run.c:57
        #2  0x4005514f in __libc_start_main () from /lib/libc.so.6
        (gdb) p /x $pc
        $1 = 0x8048582        <<<--- $pc is equal to bp #1 address

The expected output after the run command was:

        (gdb) run 1
        Starting program: [...]/gdb.base/commands 1
        factorial command-list executed
        1

        Program exited normally.
        (gdb)

The problem is that the breakpoint is deleted very early in the inferior
stop handling, so the rest of the code does not have a chance to see
that there was a temporary breakpoint there with a commands list to
execute. To fix this, it is necessary to delay a bit the deletion of
this breakpoint.
>How-To-Repeat:

>Fix:
I have a fix for this which consists into delaying the deletion of this 
breakpoint until the next stop. I will send it to gdb-patches shortly.
>Release-Note:
>Audit-Trail:
>Unformatted:


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