[fpc-devel] 2.0.4-rc3 available

Tomas Hajny XHajT03 at mbox.vol.cz
Tue Aug 15 11:45:53 CEST 2006

Dave Parsons wrote:
> On Mon, 14 Aug 2006 18:48:55 +0200 (CEST), Tomas Hajny wrote:
>> Dave Parsons wrote:
>> > On Mon, 14 Aug 2006 13:15:51 +0200 (CEST), Tomas Hajny wrote:
>> >> Dave Parsons wrote:
>> >> > On Sun, 13 Aug 2006 23:08:29 +0200, Tomas Hajny wrote:
>> 2) Function for accessing ports requires special segment in the
>> resulting
>> executable. Support for that would need to be added in internal linker,
>> but both LINK386.EXE and WLINK.EXE can handle that without problems. GDB
>> is another story - there's no GDB able to handle regular OS/2 executable
>> format (LX - based on Intel OMF). Alternative debuggers exist (e.g.
>> Watcom
>> debugger, SDD from IBM and debugger for Virtual Pascal/2), but there's
>> no
>> support for their integration with FPC so far. Out of them, only Watcom
>> debugger might be compatible with debug info format produced with FPC.
> Which format does FPC use?

STABS format is fully supported (and used for OS/2 target at the moment as
the only one supported by the old GDB), but emitter of DWARF debug info is
available in the compiler and used for some targets.

> I looked at Sibyl, which I do use, and WDSibyl as possibilities
> for OS/2 but Wolfgang seems to me to be deviating from Delphi
> compatibility rather than improving it, though there might be
> some useful ideas there.

Right. Regarding debugger, he probably doesn't support either of the two
debug info formats available in FPC at the moment (new debug info format
could be added too, but would probably mean more work).

> Has there been any discussion/attempt to get away from GDB and
> integrate a native FPC solution? Using an external debugger
> doesn't seem ideal to me.

It isn't ideal indeed. Creating a debugger requires some time, though. You
need modules for reading the individual executable formats (as used on the
different platforms), modules related to CPU-specific handling plus
modules related to platform specific handling. The docs are available,
though, as well as sources of some other debuggers (for inspiration) -
GDB, SDD386, (WD)Sibyl (written in Pascal and supporting Pascal syntax at
least), etc.


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