From: torvalds@klaava.Helsinki.FI (Linus Benedict Torvalds) Subject: Re: gdb: "Bad things happen" Date: 15 Mar 1992 21:03:10 GMT
In article <Mar.15.12.47.54.1992.3590@dartagnan.rutgers.edu> hedrick@dartagnan.rutgers.edu (Charles Hedrick) writes:
>I've been trying out gdb, from tsx-11. It's not entirely easy to
>install it, as I had to figure out what libg.a is supposed to be,
>and I had to remember to use cc1-g from the 1.40 distribution.
>But I've got something that mostly works. However when I try
>to step through a call to localtime, I get
>
> Bad things happen: nonexistent page error in do_no_page
> Segmentation fault
>
>This is the version of localtime from the BSD ctime.c, which is
>in the libc I put out on athos.rutgers.edu a couple of weeks ago.
The "bad things" error is a message that happens when the memory manager
gets a request for a page not in the users process-space, which
shouldn't be possible (as those errors should be trapped by the
segmentation handler). However, ptrace() does some mucking around with
the memory, and it had a bug (now fixed, I hope) that is probably the
reason for this. I'm happy most of it seems to work, though.
Linus