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From: Waldek Hebisch
Subject: New (gpc-20060325)
Date: 3 Apr 2006, 01:40:34

Adriaan van Os wrote:
> Waldek Hebisch wrote:
> 
> > Adriaan van Os wrote:
> >>
> >> The asmnames.pas failure is new. It doesn't fail with the  
> >> gpc-20060215.
> >> Neither does it fail with gpc-20060325 at -O1. At -O3 or -O2 the  
> >> output
> >> of the generated progam is empty. I can provide more info as needed.
> >>
> >
> > Will take deeper look at asmnames.pas failure on Monday. ATM I would
> > like to know if asmnames.pas fails also in non-pic mode?
> 
> Yes, that's what I already tried, it fails with -mdynamic-no-pic.
> 

I still do not know what is wrong with asmnames.pas. I have tried to
reproduce problem in ppc-linux, but in Linux asmnames.pas generated
correct output. I am affraid it is time to do assembly level
debugging. Could you set breakpoint in `puts' and look at its
argument. The argument should be address of S plus 8, and it
should point to the string "OK". The first question is if `puts'
gets correct address (alternativly, the content of S my be
incorrect).

If the content of S is incorrect then one may step trough the
program to verify why. AFAICS generated assembly contains
`memcpy' call and after that call data part of S should contain
the string "OK". Next the length field (at address S plus 4)
should be set to 2. Then there is a code to null terminate S
(but only in conditionally, if it is not already null terminated).
Then `puts' is called.

At first glance the assembly contains all needed instructions, but
computers are much better then people at executing programs, so
one should just single-step the program verifing values stored
in S at each step.

BTW. One gets simplest assembly using `-static -fno-range-checking'.

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