I have a program that I have written in C++ under linux (Ubuntu 10.10).
The programming and debugging worked perfectly until the moment I added the following lines to the code:
mapfile = fopen(map_filename,"wb");
fwrite(map_header,1,20,mapfile); // <-- this is the problem line
fclose(mapfile);
After I added those, the program compiles ok, but the debugger now won't start. It immediately fails with this message:
Program completed, Exit code 0x177
error while loading shared libraries: unexpected PLT reloc type 0xcc
And if I remove the line with the "fwrite", the debugger will start normally.
This problem only happends inside Netbeans.
When I debug it using the command-line "gdb" it also works ok without any problems.
Anyone have idea why its happening and how to fix it?
P.S: Those problems started recently so I assume maybe it has to do something with system updates, I'm not sure.
Found the problem:
Not long ago, I removed some old C++ projects from netbeans. It figures out that netbeans (at least v7.0) remembers all the breakpoints that I put on old projects that don't even exist in the IDE anymore.
I found this by looking at the Debugger Console (Window->Debugging->Debugging Console) and seeing that when "gdb" starts, it tries to setup all these breakpoints from other projects or from projects that do not exists (this is a bug in netbeans, btw)
The solution: I simply cleaned all the breakpoints (inside Window->Debugging->Breakpoints) and now the program can be debugged properly.
Hope this will help to anyone out there who has the similar problem.
Related
I have a weird problem with the CLion debugger.
When I put a breakpoint or two and then hit the debug button, the debugger would initialize and stop at the first breakpoint. But then when I hit any of the step buttons in the console (Step Over, Step Into), it executes the line and then it won't allow me to step any more. The debugging process is still on, but I can't in fact do anything.
It's worth mentioning that this problem occurs only with projects that I create in CLion in my computer. When a friend creates a new CLion project and shares it with me, the CLion debugger works just fine when I use it with this project in the same computer (mine).
Any clue would be appreciated!
I ran into the same problem, and it turned out single-stepping worked only for the first few lines of code - until I called gethostname() followed by WSACleanup(). When one of them was commented out, the single stepping worked fine (F7/F8).
This is on a Windows 10 machine, and the functions are part of Microsoft's WinSock implementation.
When I compile and run my code, the console window no longer shows up.
(I have "system("pause");" included, this is not the issue).
I was trying to debug a program in Dev C++ and must have changed some settings. Any advice?
Dev-C++ is really old and the debugger is full of bugs. If you're sure the problem isn't with your code, then I'm assuming you've tried the basics, like restarting Dev-C++ and restarting the computer?
If that doesn't work, try reinstalling Dev-C++... It only takes a couple seconds to install it.
You can also try stepping the code.
So, I have no idea why, but breakpoints in my code::blocks project are no longer working. I'm using MinGW-W64 compiler and GDB. I used to be able to use breakpoints, but now, for some reason, when I add them to my code they do absolutely nothing - code execution goes right past them without stopping.
Why might this be happening?
You might be compiling your code in release mode. Try changing it to debug mode. Checkout http://wiki.codeblocks.org/index.php?title=Debugging_with_Code::Blocks on how to turn on debugging symbols.
I'm really lost in here. Maybe some of you can point me to a right direction.
I'm developing a tool in ANSI C using GCC over MinGW. The tool is to be run only from command line. Probably only on windows machine. It elaborates some data locally and generates files for use by other programs. Basically it does a lot of math and a few file handling. Nothing really fancy. I didn't find it necessary posting the whole 1000+ lines here for examination...
I compile it with GCC -ansi making sure not even a single warning is present. Everything worked always well as the development evolved. But recently I started getting (almost) random segfaults. I checked for the last changes made, but found nothing. I removed the last changes completely coming back to when it perfectly worked. Still segfaults. I traced line by line. I went back to read and re-read the whole code searching for possible pointers/malloc errors. I simply can't find the reason for it to fail so often and so randomly.
So here is the strange thing - I compiled it with -g and run through GDB.
start MSYS
change dir where the program resides
$ gdb generatore.exe (the one compiled -g that fails)
$ run
And it perfectly works inside GDB. I went step by step. Line by line. Perfect. I tried stressing it with huge amounts of data. All works. Can't reproduce the error. But if the same executable is run from command line, it fails.
I suspect an unpredictable behavior with some pointer but I cannot find it anywhere.
Has anyone ever encountered anything similar? Where should I be checking? Also, I am not as familiar with GDB, since it runs smoothly, can I enforce the control somehow to find the reason it fails? Are any other free debugging solutions for windows you can advise me? How can I debug for unpredictable behaviors?
Thanks a lot for your attention,
maxim
There is a great free tool for catching all kind of runtime errors to do with pointers, memory allocations, deallocations, etc., which cannot be caught at compile time, so your compiler will not warn you about them: valgrind http://valgrind.org/. The problem is, AFAIK it doesn't run on Windows. However, if your program is pure ANSI C you should be able to build it and run it with valgrind on a Linux box.
I'm not 100% sure about it, but it should run OK in a virtual machine, so if you don't have a separate Linux computer you can try installing e.g. Ubuntu in Virtual Box or VmWare and try running your program with valgrind in it.
I encountered following problem:
I write program in c++ using VS2010. Debug build works properly when run with/without debugging in VS. When I launch built executable directly it also works.
Release build works when run with debugging in VS and alsp when I launch build executable directly.
Unfortunately, program does not work when I run release build in VS -without debugging-. Window is created and then program crashes quickly (without any error message). Since it crashes when run without debugging I don't know how to identify what causes the problem.
Any ideas what might be causing this? Thanks :)
It seems most likely you have some sort of memory error/corruption that just happens to work ok in the debugger.
You can try using couts to isolate how far/where it dies, or try a tool like Purify (or valgrind for free if you can port to Linux).