sdb: the debugger from hell...

[John Coolidge]

rmtodd at servalan.uucp (Richard Todd) writes:
>brownrigg at kuhub.cc.ukans.edu writes:
>Yep.  About the only good thing about sdb is that it is more clueful about
>handling C structures et al than its predecessor adb.

adb is still fairly useful if you want to quick-and-dirty look at
a bunch of assembly, though :-) (actually, this is often something
I want to do; it's useful when doing operating systems development
at times :-)).

>However, there is relief courtesy of your friendly next-door
>(literally) archive site, wuarchive.wustl.edu.  Lurking in the /systems/aux/
>gnu directory are executables for GDB, the GNU Debugger.  It does know from
>typecasts, groks *myPtr, has a conditional trap facility that'll blow your
>mind, and I haven't yet seen it core dump, and it's got a whole lot more 
>nice features, too.  Note that there are two versions of gdb on wuarchive;
>the one starting with "sgdb-..."  is for programs compiled with cc; the one
>starting with "gdb-..." is for programs compiled with gcc (or g++ -- gdb has
>some support for C++ debugging).  

Actually, there are three versions. gdb-3.5 exists in two versions:
the 'gdb' version which reads dbx format debugging symbols (produced
by gcc/g++ and gas) and the 'sgdb' version which reads sdb format
symbols (cc/as). gdb-3.6- exists only in the dbx format; I'm unsure
as to whether supporting sdb format symbols is a useful thing to
do (is anyone out there actually using sgdb? Or any of the compilers
that produce sdb format symbols?).

I advise using gdb-3.6-, since it does a much better job of handling
g++ and also doesn't coredump on files using shared libraries (and
in general just seems more robust). It is pretest software, though;
you should delete it in favor of 3.6 when the full release comes out
(in fact, there seems to be some doubt about 3.6; some people have
told me that they may go straight to 4.0).

I'll be off the net for at least one and perhaps three weeks (vacation;
hope to have network access in a week).

Happy holidays!

--John

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John L. Coolidge     Internet:coolidge at cs.uiuc.edu   UUCP:uiucdcs!coolidge
Of course I don't speak for the U of I (or anyone else except myself)
Copyright 1990 John L. Coolidge. Copying allowed if (and only if) attributed.
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