Path: utzoo!utgpu!cunews!bnrgate!brtph3!brchh104!brchs1!bnr.ca!rice.edu!sun-spots-request
From: sean%fiamass.ie@pucc.princeton.edu (Sean Mc grath)
Newsgroups: comp.sys.sun
Subject: Trouble with dbx on a SPARC
Keywords: Software
Message-ID: <1404@brchh104.bnr.ca>
Date: 23 Jan 91 10:36:34 GMT
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Organization: Sun-Spots
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X-Sun-Spots-Digest: Volume 10, Issue 27, message 14
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I an having trouble with dbx on a SPARC 4-65 running SUN OS 4.1.  We use
16 bit unsigned integer datatype called UINT16.  We #define it to suit the
machine we are running on.  Unfortunately, when UINT16s are passed as
paramaters on the stack dbx gets confused.  Here is a demo of the problem:

------ CODE starts here --------
#define UINT16 unsigned short
fred(a,b)
UINT16 a,b;
{ a = b; }

main()
{
fred (15,78);
}
------ CODE ends here ---------
I compile this with debugging on using
        cc -g test.c
I run up dbx :-
        dbx a.out
I set a breakpoint in fred
        stop in fred
Run it
        run
It stops in fred. So I print a
        print a
Answer 0 - incorrect
I tried
        print (UINT)a
Answer 0 - incorrect

By the way, the 386i we have gets it right.  I think it must be to do with
dbx looking at the wrong 16 bits of the 32 bit integer that is stuffed on
the stack for both a and b.  Any ideas???

Sean Mc Grath (sean@fiamass.ie)
12 Clarinda Park North
Dun Laoghaire
Co. Dublin