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digitalmars.D - Problem with writeln

reply Ivan Senji <not_my_real_mail xyz.com> writes:
Hi!

I haven't been using D for a long long long time unfortunately. Recently 
I decided to give it a try again, downloaded D2.040, setup  descent 
(btw. descent looks great) and ddbg.

After some time I managed to get my old program compiling again and it 
works great. That is... it works great when not compiled with -debug.

After a lot of commenting out debug statements i found the problematic 
line was this statement:

debug writeln(".", counter ++);

My program is an OpenGL app and this line is located in my main draw 
method. It prints the numbers (counter) up to 203 and then crashes.

Using ddbg all i was able to get is this (not really that useful to me):

Unhandled D Exception (std.stream.WriteException
  "unable to write to stream") at KERNELBASE.dll (0x75d9b727)

When i change my problematic line to

core.stdc.stdio.printf(".%d\n", counter++);

The app still prints numbers up to 203 and the stops printing to the 
console but otherwise continues to run normally (the OpenGL drawing 
part, mouse input, everything else).

Any idea what could be causing this?

Thanks!

:)
Feb 28 2010
parent reply Walter Bright <newshound1 digitalmars.com> writes:
Since printf and writeln versions both exhibit the same problem, I 
suspect the problem is elsewhere in your program.
Feb 28 2010
parent reply Ivan <ivan.senji gmail.com> writes:
On 28.2.2010 20:42, Walter Bright wrote:

 Since printf and writeln versions both exhibit the same problem, I
 suspect the problem is elsewhere in your program.


That wouldn't surprise me :)

But I am having some problems figuring this out. Somehow playing with 
ddbg i was able to get this stack trace:


from KERNEL32.dll

C:\dmd2\windows\bin\..\..\src\phobos\std\contracts.d:147 from deh

_D3std5stdio4File17LockingTextWriter12__T3putTAxaZ3putMFAxaZv () at 
C:\dmd2\windows\bin\..\..\src\phobos\std\contracts.d:147

_D3std6format65__T19writeUpToFormatSpecTS3std5stdio4File17LockingTextWriterTAxaZ19writeUpToFormatSpecFKS3std5stdio4File17Loc
ingTextWriterKAxaZv 
() at C:\dmd2\windows\bin\..\..\src\phobos\std\format.d:1724

_D3std6format62__T14formattedWriteTS3std5stdio4File17LockingTextWriterTaTAyaZ14formattedWriteFKS3std5stdio4File17Locki
gTextWriterAxaAyaZv 
(w = 0x0013fdb8, fmt = "Exception was: %s", _param_2 = "unable to write 
to stream") at C:\dmd2\windows\bin\..\..\src\phobos\std\format.d:2189

_D3std5stdio4File21__T8writeflnTAyaTAyaZ8writeflnMFAyaAyaZv () at 
C:\dmd2\windows\bin\..\..\src\phobos\std\stdio.d:581

(_param_0 = "Exception was: %s", _param_1 = "unable to write to stream") 
at C:\dmd2\windows\bin\..\..\src\phobos\std\stdio.d:1310

   [0] = "D:\\ivans\\Projects\\D\\eclipse-workspace-d\\ifs3d\\ifs3d.exe"
}) at ivan\ifs3d\ifs3d.d:98

runMain(void*) () from dmain2

runAll(void*) () from dmain2




The part of code in my main method is this:

	try {
		writefln("Starting main loop...");
		global.loop.start();
		writefln("Main loop finished...");
	} catch(Exception e) {
		writefln("Exception was: %s", e.msg);
	}

 From what I can see an exception was thrown ("unable to write to 
stream") and the only line I added to the loop is this:

	writefln(". %s", counter++);

If that line is removed, an exception seams to be thrown from the line
	writefln("Main loop finished...");

And this is the exception:

Unhandled D Exception (std.contracts.ErrnoException
  "C:\dmd2\windows\bin\..\..\src\phobos\std\stdio.d(896):  (No error)") 
at KERNEL32.dll (0x7c812afb) thread(3548)

Has anyone ever had an exception like this? Any tips on debugging?
Mar 01 2010
parent reply "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Mon, 01 Mar 2010 04:11:28 -0500, Ivan <ivan.senji gmail.com> wrote:


 The part of code in my main method is this:

 	try {
 		writefln("Starting main loop...");
 		global.loop.start();
 		writefln("Main loop finished...");
 	} catch(Exception e) {
 		writefln("Exception was: %s", e.msg);
 	}

  From what I can see an exception was thrown ("unable to write to  
 stream") and the only line I added to the loop is this:

 	writefln(". %s", counter++);

 If that line is removed, an exception seams to be thrown from the line
 	writefln("Main loop finished...");


Post more code.  I suspect you are messing up something.  It appears that  
you may be closing stdout, but I can't be sure because your code is not  
complete.

-Steve
Mar 01 2010
parent reply Ivan <ivan.senji gmail.com> writes:
On 1.3.2010 12:47, Steven Schveighoffer wrote:

 On Mon, 01 Mar 2010 04:11:28 -0500, Ivan <ivan.senji gmail.com> wrote:


 The part of code in my main method is this:

 try {
 writefln("Starting main loop...");
 global.loop.start();
 writefln("Main loop finished...");
 } catch(Exception e) {
 writefln("Exception was: %s", e.msg);
 }

 From what I can see an exception was thrown ("unable to write to
 stream") and the only line I added to the loop is this:

 writefln(". %s", counter++);

 If that line is removed, an exception seams to be thrown from the line
 writefln("Main loop finished...");


 Post more code. I suspect you are messing up something. It appears that
 you may be closing stdout, but I can't be sure because your code is not
 complete.


The code can be seen here: http://github.com/ivans/ifs3D
I didn't and still don't want to bother anyone too much. :)

It should compile on windows with a command found in a readme file.

I don't think I am closing stdout anywhere and I probably am doing 
something wrong somewhere, but can't figure out where and what.
Mar 01 2010
parent reply "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Mon, 01 Mar 2010 07:14:23 -0500, Ivan <ivan.senji gmail.com> wrote:


 On 1.3.2010 12:47, Steven Schveighoffer wrote:

 On Mon, 01 Mar 2010 04:11:28 -0500, Ivan <ivan.senji gmail.com> wrote:


 The part of code in my main method is this:

 try {
 writefln("Starting main loop...");
 global.loop.start();
 writefln("Main loop finished...");
 } catch(Exception e) {
 writefln("Exception was: %s", e.msg);
 }

 From what I can see an exception was thrown ("unable to write to
 stream") and the only line I added to the loop is this:

 writefln(". %s", counter++);

 If that line is removed, an exception seams to be thrown from the line
 writefln("Main loop finished...");


 Post more code. I suspect you are messing up something. It appears that
 you may be closing stdout, but I can't be sure because your code is not
 complete.


 The code can be seen here: http://github.com/ivans/ifs3D
 I didn't and still don't want to bother anyone too much. :)

 It should compile on windows with a command found in a readme file.

 I don't think I am closing stdout anywhere and I probably am doing  
 something wrong somewhere, but can't figure out where and what.


Your code is too complex for me to understand quickly :)

Comment out other lines until you figure out which one closes it.

Start with commenting out the entire loop :)  If that then works, you know  
something inside the loop is killing stdout.

BTW, are you compiling in Windows mode?  I.e. do you see a console on the  
screen when you run it?  If not, then there is no stdout or stdin.  From  
your command line in the readme, I don't think you are.  However, in that  
case, I don't think you'd get anywhere or see any output.

-Steve
Mar 01 2010
parent reply Ivan <ivan.senji gmail.com> writes:
On 1.3.2010 14:43, Steven Schveighoffer wrote:

 On Mon, 01 Mar 2010 07:14:23 -0500, Ivan <ivan.senji gmail.com> wrote:


 On 1.3.2010 12:47, Steven Schveighoffer wrote:

 On Mon, 01 Mar 2010 04:11:28 -0500, Ivan <ivan.senji gmail.com> wrote:


 The part of code in my main method is this:

 try {
 writefln("Starting main loop...");
 global.loop.start();
 writefln("Main loop finished...");
 } catch(Exception e) {
 writefln("Exception was: %s", e.msg);
 }

 From what I can see an exception was thrown ("unable to write to
 stream") and the only line I added to the loop is this:

 writefln(". %s", counter++);

 If that line is removed, an exception seams to be thrown from the line
 writefln("Main loop finished...");


 Post more code. I suspect you are messing up something. It appears that
 you may be closing stdout, but I can't be sure because your code is not
 complete.


 The code can be seen here: http://github.com/ivans/ifs3D
 I didn't and still don't want to bother anyone too much. :)

 It should compile on windows with a command found in a readme file.

 I don't think I am closing stdout anywhere and I probably am doing
 something wrong somewhere, but can't figure out where and what.


 Your code is too complex for me to understand quickly :)

 Comment out other lines until you figure out which one closes it.

 Start with commenting out the entire loop :) If that then works, you
 know something inside the loop is killing stdout.

 BTW, are you compiling in Windows mode? I.e. do you see a console on the
 screen when you run it? If not, then there is no stdout or stdin. From
 your command line in the readme, I don't think you are. However, in that
 case, I don't think you'd get anywhere or see any output.


Thank you for helping. I did what you suggested and started commenting 
out code to get it working. I finally got to a working code with just 
two lines commented out:

http://github.com/ivans/ifs3D/commit/339ca5ee58661d636bfcd878c08b06bacede7dca

These lines have nothing to do with streams and stdout, so I still don't 
understand what is going on. But this part of code is very old and 
stupid (allocating a lot of unneccessary real[][]'s) so I guess the next 
step is to figure out a smarter way to do that part and see if the 
exception goes away :).

Uh I have missed debuging D programs :).
Mar 01 2010
parent reply "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Mon, 01 Mar 2010 10:42:00 -0500, Ivan <ivan.senji gmail.com> wrote:


 On 1.3.2010 14:43, Steven Schveighoffer wrote:

 On Mon, 01 Mar 2010 07:14:23 -0500, Ivan <ivan.senji gmail.com> wrote:


 On 1.3.2010 12:47, Steven Schveighoffer wrote:

 On Mon, 01 Mar 2010 04:11:28 -0500, Ivan <ivan.senji gmail.com> wrote:


 The part of code in my main method is this:

 try {
 writefln("Starting main loop...");
 global.loop.start();
 writefln("Main loop finished...");
 } catch(Exception e) {
 writefln("Exception was: %s", e.msg);
 }

 From what I can see an exception was thrown ("unable to write to
 stream") and the only line I added to the loop is this:

 writefln(". %s", counter++);

 If that line is removed, an exception seams to be thrown from the  
 line
 writefln("Main loop finished...");


 Post more code. I suspect you are messing up something. It appears  
 that
 you may be closing stdout, but I can't be sure because your code is  
 not
 complete.


 The code can be seen here: http://github.com/ivans/ifs3D
 I didn't and still don't want to bother anyone too much. :)

 It should compile on windows with a command found in a readme file.

 I don't think I am closing stdout anywhere and I probably am doing
 something wrong somewhere, but can't figure out where and what.


 Your code is too complex for me to understand quickly :)

 Comment out other lines until you figure out which one closes it.

 Start with commenting out the entire loop :) If that then works, you
 know something inside the loop is killing stdout.

 BTW, are you compiling in Windows mode? I.e. do you see a console on the
 screen when you run it? If not, then there is no stdout or stdin. From
 your command line in the readme, I don't think you are. However, in that
 case, I don't think you'd get anywhere or see any output.


 Thank you for helping. I did what you suggested and started commenting  
 out code to get it working. I finally got to a working code with just  
 two lines commented out:

 http://github.com/ivans/ifs3D/commit/339ca5ee58661d636bfcd878c08b06bacede7dca

 These lines have nothing to do with streams and stdout, so I still don't  
 understand what is going on. But this part of code is very old and  
 stupid (allocating a lot of unneccessary real[][]'s) so I guess the next  
 step is to figure out a smarter way to do that part and see if the  
 exception goes away :).


I suspect there may be a bug in dmd when dealing with reals, specifically  
with your array creation routine.

That code doesn't seem to be incorrect by any means.

Try building the resulting arrays manually (that is, instead of using that  
array template function), and see if it helps.

Also, try removing the calls to the inner sq function (BTW, you don't need  
to make that an inner function, doing so unnecessarily complicates things).

If you can find the thing that fixes it, we may be able to find a reduced  
test case.  Also, try upgrading your compiler to the latest if you haven't  
already.

-Steve
Mar 01 2010
parent Ivan <ivan.senji gmail.com> writes:
On 1.3.2010 17:15, Steven Schveighoffer wrote:

 On Mon, 01 Mar 2010 10:42:00 -0500, Ivan <ivan.senji gmail.com> wrote:


 On 1.3.2010 14:43, Steven Schveighoffer wrote:

 On Mon, 01 Mar 2010 07:14:23 -0500, Ivan <ivan.senji gmail.com> wrote:


 On 1.3.2010 12:47, Steven Schveighoffer wrote:

 On Mon, 01 Mar 2010 04:11:28 -0500, Ivan <ivan.senji gmail.com> wrote:


 The part of code in my main method is this:

 try {
 writefln("Starting main loop...");
 global.loop.start();
 writefln("Main loop finished...");
 } catch(Exception e) {
 writefln("Exception was: %s", e.msg);
 }

 From what I can see an exception was thrown ("unable to write to
 stream") and the only line I added to the loop is this:

 writefln(". %s", counter++);

 If that line is removed, an exception seams to be thrown from the
 line
 writefln("Main loop finished...");


 Post more code. I suspect you are messing up something. It appears
 that
 you may be closing stdout, but I can't be sure because your code is
 not
 complete.


 The code can be seen here: http://github.com/ivans/ifs3D
 I didn't and still don't want to bother anyone too much. :)

 It should compile on windows with a command found in a readme file.

 I don't think I am closing stdout anywhere and I probably am doing
 something wrong somewhere, but can't figure out where and what.


 Your code is too complex for me to understand quickly :)

 Comment out other lines until you figure out which one closes it.

 Start with commenting out the entire loop :) If that then works, you
 know something inside the loop is killing stdout.

 BTW, are you compiling in Windows mode? I.e. do you see a console on the
 screen when you run it? If not, then there is no stdout or stdin. From
 your command line in the readme, I don't think you are. However, in that
 case, I don't think you'd get anywhere or see any output.


 Thank you for helping. I did what you suggested and started commenting
 out code to get it working. I finally got to a working code with just
 two lines commented out:

 http://github.com/ivans/ifs3D/commit/339ca5ee58661d636bfcd878c08b06bacede7dca


 These lines have nothing to do with streams and stdout, so I still
 don't understand what is going on. But this part of code is very old
 and stupid (allocating a lot of unneccessary real[][]'s) so I guess
 the next step is to figure out a smarter way to do that part and see
 if the exception goes away :).


 I suspect there may be a bug in dmd when dealing with reals,
 specifically with your array creation routine.

 That code doesn't seem to be incorrect by any means.

 Try building the resulting arrays manually (that is, instead of using
 that array template function), and see if it helps.

 Also, try removing the calls to the inner sq function (BTW, you don't
 need to make that an inner function, doing so unnecessarily complicates
 things).

 If you can find the thing that fixes it, we may be able to find a
 reduced test case. Also, try upgrading your compiler to the latest if
 you haven't already.


The problem wasn't with reals. I added an alias so I can easily change 
my floating point type and application crashed with all of them, but 
after a diferent amount of iterations.

I managed to get rid of the problem by removing a lot of dynamic array 
allocations and I am now mostly using static arrays. I still have this 
same problem in another peace of that same program and will still try to 
get a reproducable and small test case.

Thanks for all the help and good advice. :)
Mar 05 2010