Dealing with full-screen crashes on Mac, using command-line LLDB - c++

I'm trying to debug a crash in a full-screen Mac game I'm working on, but when I have LLDB attached it just causes the game to freeze when the crash happens, and I can't get away from the game - I need to do a hard reset on the computer. Is there any kind of tool or preference for doing this? The computer I'm using to reproduce the crash doesn't have multiple monitors.

Can you do two-computer debugging? Set up an ssh account on the game-running machine, log in to it remotely (command line in Terminal) from your not-game-running machine, run command line lldb on your game. (process attach -n <appname>)
In the past, with gdb, Xcode had support for "remote debugging" which was this arrangement (Xcode running on one Mac, your full-screen game on the other) assuming you already had ssh configured correctly. I don't believe Xcode currently supports remote debugging with lldb - I'd encourage you to file a bug report at http://bugreport.apple.com/ registering your need for this feature if it's something you need in your workflow.
I'm afraid I can't think of any answers for you off-hand if you're doing single-machine debugging.

Related

Debug remotely on STM32CubeIDE with an STM32 eval board

I want to setup the following environment: I've got a STM32H753I-EVAL2 eval board, connected on a Windows PC. Until now I was developping and debugging locally on this PC with STM32CubeIDE. For several reasons my code source is on a Linux server (Samba mounting) so it takes forever to build a project. Hence I want to develop on the linux server from my Windows machine.
Compiling is working fine (and is way faster) but the issue is about debugging. I know it is possible to debug remotely, the Debug Configuration window from Eclipse (I'm using OpenOcd) allows to connect to a remote GDB server. What I don't know is how to start a GDB server on the Windows machine that will connect to the STM32 board ?
Sorry for the "answer to myself" but I think it might be useful for others (and even to me when I have forgotten in a few weeks ;) ).
Here is how to do.
on host side (on the machine where the eval board is physically plugged in) you have to manually launch the GDB server application that comes with STM32CubeIDE installation. See STMicro application note UM2576 for details. The default command line is:
ST-LINK_gdbserver.exe -d -v -cp "C:\ST\STM32CubeIDE_1.0.0.19w12patch\STM32CubeIDE\plugins\com.st.stm32cube.ide.mcu.externaltools.cubeprogrammer.win32_1.0.0.201903011553\tools\bin"
Now you've done the hardest. On server/remote side you have to setup the Debug Configuration to use OpenOcd with option "Connect to remote GDB server" and simply enter IP address and port number (which is not 3333 by default but 61234, but it can be modified).
This setup is working fine, even if I encoutered some instabilities during debugging once in a while.
I see two (maybe three) options
Use an alternate GDB server (see below)
Run the GDB server from STMCubeIDE in isolation (see OP's answer for Windows, this answer for Linux)
GDB Serial (not really an option right now but I'll share my experience so far)
I have used the second option to succesfully debug my target using arbitary GDBs such as gdb-multiarch command line and in the (non STMCube-ified) Eclipse CDT
Alternative GDB Servers
You could try STLink open source. I did. The problem is, your device might not be supported properly. I built 1.6.1 from Github to enable support for STM32G03x device. While moving to this version enabled it to detect the device, and I can use st-flash to program the device, the debugger is unusable (try and alter a register, it alters the wrong one, try and single step a program, it crashes immediately).
Do try it though .. it's easy and quick to install (or build), so it's worth checking if your device will work correctly with it.
Openocd is another option, but seems not to support SWD connection. I tried a build that allegedly had a patch for this but no luck.
If you can get one of these open source alternatives to work, they have another advantage, you may be able run them on something like a Raspberry PI, which means you don't have to get a PC physically close to your target.
Run the GDB server from STMCubeIDE in isolation
For Windows, see the OP's answer. For Linux, I do this alter the pathnames to suit your installation
LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/home/user/apps/st/stm32cubeide_1.5.1/plugins/com.st.stm32cube.ide.mcu.externaltools.stlink-gdb-server.linux64_1.5.0.202011040924/tools/bin/native/linux_x64/ /home/user/apps/st/stm32cubeide_1.5.1/plugins/com.st.stm32cube.ide.mcu.externaltools.stlink-gdb-server.linux64_1.5.0.202011040924/tools/bin/ST-LINK_gdbserver -p 61234 -l 1 -d -s -cp /home/user/apps/st/stm32cubeide_1.5.1/plugins/com.st.stm32cube.ide.mcu.externaltools.cubeprogrammer.linux64_1.5.0.202011040924/tools/bin -m 0 -k
How did I get to this? Firstly launched a debugging session from STMCubeIDE, then ran
ps aux | grep gdbserver
Then we can see how Eclipse (STMCube) is launching the gdbserver and work from there.
If you find it complains about a .so file, locate that file from the STMCube installation and ensure the path to the directory containing it is in LD_LIBRARY_PATH (as per my example)
You can also launch the program with --help to show more options.
If add -e (persistent) you can disconnect and reconnect a GDB client without resetting the target (it will reset on initial invocation of the gdb server though, even without -k).
GDB Serial
This is where the target implements the GDB server end of the protocol. The GDB stub usually runs in an exception handler. This would usually be your breakpoint handler but you can also make it the default handler for unhandled exceptions, or, for example, the ctrl-c interrupt.
I have done a lot of Googling about this recently and basically when people ask about it on forums they usually get responses along the lines of "Here be dragons" or "Why don't you use JTAG?"
So the drivers for this, you might like to know, are in the GDB sources git://sourceware.org/git/binutils-gdb.git under gdb/stubs. The documentation is here. There isn't a stub implementation there for arm. Which is sad really, I used to use GDB remote serial regularly where I worked, and some of those targets were indeed ARM. The operating system was ecos.
So could ecos GDB stubs be ported to bare metal? Having giving it a good coat of looking at, I believe yes they could. The stubs are based on the ones from the GDB sources but they are heavily polluted with Ecos and Redboot build macros and copyright (the ogiringals were written by HP and released without copyright). We don't know what bugs the Ecos stubs may contain (I fixed at least one back in the day and I don't recall whether I submitted a patch). We don't know if they really support the latests architectures properly. And, we don't know if, after that, they simply use up too much memory - my STM32 has 8K of SRAM and I already see buffers that have a default size of 2K (not saying that's necessary but you see how work needs to be done here..)
So this third option, I will revisit this one day but for now, for me, it's a nope.

Eclipse Remote Debugging CDT tutorial

TL;DR: is there a step by step tutorial to do remote code debugging using Eclipse Neon?
I have the source code in a Linux machine with a GCC dev environment. Normally, I ssh to the box, edit the file, and compile/debug using gdb, and it works, but it is a bit clunky for me.
I am now trying to debug the code from my Windows machine using the latest Eclipse version (Neon as of this writing).
I've tried following the instructions online (like this one), but they all seem to point towards (cross-)compiling the code locally, deploying it remotely and debugging there. This is not what I'm after. I essentially want to use Eclipse as a remote text editor+gdb interface, with the building and compiling being done in the remote system.
I've installed CDT, plus pretty much any plugin remotely related to remote development
Remote System Explorer
Remote Launch
GCC Cross compiler support
Remote (over TCF/TE) Run/Debug Launcher
Direct Remote C++ Debugging
TCF C/C++ Debugger
TM Terminal
So far, I can connect to the remote system, create a Remote Project and edit the source code.
I don't need Eclipse to compile the code (I can do that separately) but I'm unable to debug the code.
Using C/C++ Remote Application fails in many creative ways when trying to find gdb in the remote system.
Using GDB (DSF) Automatic Remote Debugging Launcher ends in a java.lang.NullPointerException, which also invalidates the configuration
Using Direct Remote Debugging Launcher asks about a remote workspace, then complains with "Error with command: gdb --version Cannot run program "gdb": Launching failed"
Remote Application complains about the Process/Image field. Setting it to the binary output doesn't enable the Debug button, so no dice.
TCF is dead in the water. It doesn't recognize the SSH connections I set up on RSE, it asks for the username password (I use public keys) and root password (?!) Even when entering that info, it fails to continue.
On a whim, I tried NetBeans, and followed the instructions here, and got it working in five minutes. The mode I'm following is the "Full Remote Development" according to NetBeans. The reason I'll still need to stick to Eclipse is that it is the dev environment that we use in the company, and it makes little sense to me to add another IDE to do something that Eclipse by all rights should do no problem.
What I find is that the walkthroughs for Eclipse I've found are either
Using plugins that are now either deprecated, not supported or have been completely reworked. Eclipse crashes and burns on these.
Trying to compile locally and deploy remotely, doing things like embedded even, but that's not what I'm looking for.
Using the Eclipse DStore client-server combo, which is essentially an alternative to SSH, but not what I'm looking for either.
I'm then hoping someone has written/found a tutorial that is relatively simple to follow (it is, after all, a relatively simple thing to do, as NetBeans has proven), and that works on any version of Eclipse.
I'll consider using an older version of Eclipse, but if so, please be specific in which version I should use, and which plugins I should install.

CLion run program in separate system terminal

I have an ncurses program that I'd like to interactively debug using CLion. The problem is that when I run the program in CLion to debug it, the inbuilt console where the program is run doesn't display the output of the ncurses program properly.
I'd like to have the program run in my systems terminal so I can see the output properly whilst debugging the program with CLions debugger.
Is there any way to do this?
The best way to accomplish this is to use GDB now it can be really frustrating to get started so Ill show you how I accomplished it in linux
open a terminal and go to your project debug file and type gdbserver localhost:1234 ./myFile
open clion to myFile project and in the upper right corner you should see a build all (or your projects name) click it and go to "edit configurations"
in the upper left corner you should see a plus sign, click it and press "GDB remote debug"
then in "target remote" type tcp:127.0.0.1:1234
Next in "path mappings" press the plus and type /location/to/file/myFile (same file as in 1.) in both Remote and Location
Press OK and in the upper right corner select the name of the configuration that you just made and press debug
you might need to try to restart the gdbserver one more time for this to work but if you did all the steps above you should see a debug prompt come up and on the terminal you should see your project running.
There are some limitations with this for example you always have to run gdbserver localhost:1234 ./myFile command on your terminal for it to work.
Some Video/documentation that helped me:
Debugging with GDB at 33:35 (Video by JetBrain)
GDB documentation on Jetbrain
I hope this helped :)
In other debuggers, you would do this by running the ncurses application in a terminal, and attaching the debugger to the process using ncurses.
Doing that avoids interference between ncurses (which changes the terminal I/O modes) and the debugger's command-line.
The attach feature is a recently released feature of the CLions debugger:
Further reading:
More power to debug: Attach to local process (January 20, 2016)
CLion 1.2 roadmap (August 31, 2015)
Debugging in CLion (May 8, 2015 )
CLion answers frequently asked questions (September 16, 2014)
Debugging ncurses application with gdb
Using GNU's GDB Debugger:
Debugging Ncurses Programs

Debugging embedded device

I work on an embedded device on powerPC with WindRiver linux.
Almost always we debug using the logs. Sometimes gdb, which is really helpful.
But, the process I debug runs with more than 70 threads.
Using commands to move through the code is a cumbersome process, installing a GUI front end is not an option.
Is there any way that I can have an IDE like ECLIPSE, Netbeans to debug the process, which is running on this embedded device?
Is there any way that I can have an IDE like ECLIPSE, Netbeans
Yes. Many people debug embedded devices with Eclipse, by using gdbserver.

How to do remote debugging with Eclipse CDT without gdbserver?

We're using the Eclipse CDT 5 C++ IDE on Windows to develop a C++ application on a remote AIX host.
Eclipse CDT has the ability to perform remote debugging using gdbserver. Unfortunately, gdbserver is not supported on AIX.
Is anyone familiar with a way to debug remotely using Eclipse CDT without gdbserver? Perhaps using an SSH shell connection to gdb?
finally I got gdb run remotly anyhow now. At the Bug-symbol on the taskbar I took Debug Configurations - GDB Hardware Debugging.
In Main C/C++ Applications I set the full path on the Samba share of the executable (X:\abin\vlmi9506). I also set a linked folder on X:\abin in the project. Then I modified my batch-script in GDB Setup. It's not directly calling gdb in the plink-session but a unix-shell-script, which opens gdb. By this I have the possibility to set some unix environment-variables for the program before doing debug. The call in my batch:
plink.exe prevoax1 -l suttera -pw XXXXX -i /proj/user/dev/suttera/vl/9506/test/vlmi9506ddd.run 20155 dev o m
In the unix script I started gdb with the command line params from eclipse, that I found in my former tryals. The call in the shell command looks like this:
gdb -nw -i mi -cd=$LVarPathExec $LVarPathExec/vlmi9506
Then IBM just gives gdb 6.0 for AIX. I found version 6.8 in the net at http://www.perzl.org/aix/index.php?n=Main.Gdb. Our Admin installed it.
I can now step through the program and watch variables. I even can write gdb-commands directly in the console-view. yabadabadooooooo
Hope that helps to others as well. Can not tell, what was really the winner-action.
But each answer gives more new questions. Now I got 3 of them.
When I start the debug config I have to click restart in the toolbar to come really in the main procedure. Is it possible to come directly in main without restarting?
On AIX our programs are first preprocessed for embedded sql. The preprocessed c-source is put in another directory. When I duble-click the line to set a breakpoint, I get the warning "unresolved breakpoint" and in the gdb-console I see, that the break is set to the preprocessed source which is wrong. Is it possible to set the breakpoints on the right source?
We are using CICS on AIX. With the xldb-Debugger and the CDCN-command of CICS we manage that debugging is started, when we come in our programs. Is it possible to get that remotely (in plink) with gdb-eclipse as well?
I wouldn't normally take a shot in the dark on a question I can't really test the answer to, but since this one has sat around for a day, I'll give it a shot. It seems from looking at:
http://wiki.eclipse.org/TM_and_RSE_FAQ#How_can_I_do_Remote_Debugging_with_CDT.3F
...that even if the CDT has changed since that wiki page was made, you should still be able to change the debug command to:
ssh remotehost gdb
instead of using TM which uses gdbserver. This will probably be slightly slower than the TM remote debugging since that actually uses a local gdb, but on the other hand this way you won't have to NFS or SMB mount your source code to make it available to the local debugger (and if you're on a LAN it probably won't matter anyhow).
There's also a reference TCF implementation for linux, which you may or may not have any luck recompiling for AIX, but it allows for remote debugging if gdbserver is otherwise not available:
http://wiki.eclipse.org/DSDP/TM/TCF_FAQ
tried also to remotly debug an aix-appl with windows eclipse-cdt-gdb.
Got blocked at the end with unix/windows path-problems. Maybe my result can help u a little further - maybe you already got it work. I'm interested in your comment. asked on eclipse news portal- following the answer of martin oberhuber (thanks again) tried dsp dd (also blocked with path problem) and set an request in eclipse bugzilla.
here the link to news:
http://www.eclipse.org/newsportal/article.php?id=406&group=eclipse.dsdp.tm
Here my bugzilla:
https://bugs.eclipse.org/bugs/show_bug.cgi?id=252758
At the moment we still debug localy with xldb but I am trying ddd-gdb at the moment. At least locally gdb is running.