[fpc-pascal] Carbon: GetTextExtentPoint and Access Violation (major show stopper)

[Jonas Maebe]

On 26 Jun 2008, at 10:56, Bent Normann Olsen wrote:

> I can't reproduce the crash on a test program, so I suspect it has  
> to do
> with large applications with tons of strings.

It's most likely due to memory corruption in the large application  
caused by a bug in it.

> Could FPC have troubles handling strings?

It could of course, but there are no known issues with it.

> And should I change our handlings
> of strings to a certain type of strings before setting text  
> properties of
> controls?

No.

> Any clue or help is much appreciated.

You could try compiling your program (and possibly the lcl) with -gttt  
to turn on filling local variables and out parameters with garbage,  
which may help in case the problem is an uninitialised value. Another  
option is -gh to turn on memory debugging, possibly also adding  
"keepreleased:=true" to your program initialisation code (but in that  
case watch the memory usage, as no memory will really be released in  
that case).

Another interesting approach might be looking for Pascal support in  
Delta (http://delta.tigris.org/) to automatically reduce the large  
program to a smaller one which still demonstrates the problem.


Jonas