Date: Thu, 8 Aug 1996 10:54:29 +0200 (IST) From: Eli Zaretskii To: David M Barrett Cc: djgpp AT delorie DOT com Subject: Re: Enhanced FSDB Questions In-Reply-To: <4tobm6$psp@srvr1.engin.umich.edu> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII On 31 Jul 1996, David M Barrett wrote: > - Is this program stable for other people? I'm running it under Win NT > 3.51 with 32 megs o' ram on a Dell P90. Sometimes I'm running perhaps a > telnet application in the background, but the system is mainly just a dos > window. I get random errors such as : > o When I set a breakpoint and press F9 to run up to the breakpoint, > everything is fine. But, if I just press F4 on the line I want to run > to, it gets an exception. There are similar problems under Windows 3.x (but not Windows 95, I'm told), so maybe NT has the same problem as 3.x. Try setting no more than 3 breakpoints (including the temporary breakpoint used when you single-step) and see if that makes the problems go away. If so, the cause is that the breakpoint opcode causes an interrupt (as opposed to exception) on some versions of Windows, and the current version of DJGPP debugging support expects to get an exception. For the first 3 breakpoints FSDB sets, it uses debug registers, which don't have these problems, but after that it begins using the breakpoint opcode. There is no work-around currently (except to use 3 breakpoints or less) for the above problems. Somebody should fix the DJGPP debug support for this to be solved.