[fpc-devel] Console problem in Lazarus trunk

[Pascal Riekenberg]

> Martin Frb <lazarus at mfriebe.de> hat am 28. Juli 2020 um 01:52 geschrieben:
> 
> 
> On 25/07/2020 20:40, J. Gareth Moreton wrote:
> > Hi everyone,
> >
> > This is likely due to something peculiar in my configuration that I 
> > haven't found yet, but I can't be sure.  I'm having problems in that 
> > the latest Lazarus trunk won't create a console window when I'm 
> > running the compiler source in the debugger.  I tried to jury-rig it 
> > to create its own using the AllocConsole() Windows API function as a 
> > temporary workaround, but it failed with an "access denied" error.  
> > The little I could find on that error implies that the application 
> > already has a console, but it's not displayed. Anyone got any ideas?
> 
> I did a bit of testing.
> 
> Using FpDebug => fine

Didn't noticed that the console window of the IDE was used when
run without debugger. I use fpDebug. So everything is fine here.
Sorry for the confusion!

> Using GDB:
> - IDE compiled with console => fine
> - IDE compiled without console => app in debugger does not open console.
> 
> I tried other Process.Opitons in
> components\lazdebuggergdbmi\cmdlinedebugger.pp
> function TCmdLineDebugger.CreateDebugProcess(const AOptions: String): 
> Boolean;
>        FDbgProcess.Options:= [poUsePipes, poNoConsole, poStdErrToOutPut, 
> poNewProcessGroup];
> 
> poNewConsole instead of poNoConsole made no diff.
> Adding poRunIdle => no diff
> 
>        FDbgProcess.ShowWindow := swoNone;
> swoNormal made no diff.
> 
> Besides those would affect gdb, but maybe they also are seen by Windows 
> when launching the target.
> - One possibility is that TProcess changed, and hands something 
> different to windows.
> - Another option is, that the change is in how the debugged app 
> communicates to windows that it wants a console.
> But I do not know.....
> 
> One thing I found
> components\lazdebuggergdbmi\gdbmidebugger.pp
> line 3545
>    // for win32, turn off a new console otherwise breaking gdb will fail
>    // ignore the error on other platforms
>    FSuccess := ExecuteCommand('-gdb-set new-console off', R);
> 
> Make that "on" and it works (only tested if IDE has no console).
> 
> But it is there, because at the time of creating it, it caused issues. 
> So changing it would likely cause issues on some older systems.
> There are countless combinations of
> - Windows version/bitness
> - gdb version
> - fpc version
> - app and/or ide has console or not
> And no idea how many of them may break. Maybe its just some Win95. Maybe 
> its some still supported versions.
> 
> So for now, anyone wanting to test this can change that line.
> If you do, please report your experience, and all versions in your setup.
> 
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