X-Authentication-Warning: delorie.com: mailnull set sender to djgpp-workers-bounces using -f Message-ID: <3C8118C3.C4EF9685@yahoo.com> Date: Sat, 02 Mar 2002 13:24:03 -0500 From: CBFalconer Organization: Ched Research X-Mailer: Mozilla 4.75 [en] (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: djgpp-workers AT delorie DOT com Subject: Re: Malloc/free DJGPP code References: <10203021522 DOT AA15526 AT clio DOT rice DOT edu> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Reply-To: djgpp-workers AT delorie DOT com Charles Sandmann wrote: > > > > Date: Fri, 01 Mar 2002 16:26:35 -0500 > > > From: CBFalconer > > > > > > The point of the > > > SIGSEGV would be that the rest of the system would provide a > > > traceback, while a message to stderr would not. > > > > That's why I suggested SIGABRT instead: it also produces a traceback. > > SIGABRT is fine, but I'd also like to see a message why the abort > happened, something like: > > Malloc memory control structures are corrupt, probably due to program > writing data beyond the end of the allocated data. > > or > > Attempt to free a memory block not allocated with malloc. > > Real exceptions happen because we didn't catch them - so we show everything > we know about it. If we are going to raise an exception, lets tell the > user why, instead of making it hard to understand. Only a few dozen > people really understand our register dump and trace stuff and why it's > our gift to them :-) No great sweat doing that, but as I discovered early on malloc is used during initialization and if any errors occur then writing to stdout at least is fatal and useless. If I have to put back in the debug printout mechanism for that feature the code will grow considerably. I assume write to the stderr handle will work as well as write to the stdout handle (not fwrite to streams). -- Chuck F (cbfalconer AT yahoo DOT com) (cbfalconer AT XXXXworldnet DOT att DOT net) Available for consulting/temporary embedded and systems. (Remove "XXXX" from reply address. yahoo works unmodified) mailto:uce AT ftc DOT gov (for spambots to harvest)