debug.txt ForVim version 9.1. Last change: 2024 May 11VIM REFERENCE MANUAL by Bram MoolenaarDebugging Vimdebug-vimThisis for debugging Vim itself, whenit doesn't work properly.For debugging Vim scripts, functions, etc. seedebug-scripts1. Location ofa crash, using gcc andgdbdebug-gcc2. Locating memory leaksdebug-leaks3. Windows Bug Reportingdebug-win32==============================================================================1. Location ofa crash, using gcc andgdbdebug-gccgdbWhen Vim crashes in one of the test files, and you are using gcc forcompilation, hereis what you cando to find out exactly where Vim crashes.This also applies when using the MingW tools.1. Compile Vim with the "-g" option (thereisa line in the src/Makefile for this, which you can uncomment). Also make sure "strip"is disabled (do notinstall it, or use the line "STRIP= /bin/true").2. Execute these commands (replace "11" with the test that fails):cd testdirgdb ../vimrun -u unix.vim -U NONE -s dotest.in test11.in3. Check where Vim crashes,gdb should givea message for this.4. Geta stack trace fromgdb with this command:where You can check out different places in the stack trace with:frame 3Replace "3" with one of the numbers in the stack trace.==============================================================================2. Locating memory leaksdebug-leaksvalgrindIf you suspect Vimis leaking memory and you are using Linux, thevalgrindtoolis very useful to pinpoint memory leaks.First of all, build Vim with EXITFREE defined. Search for this in MAKEFILEand uncomment the line.Use this command to start Vim:valgrind --log-file=valgrind.log --leak-check=full ./vimNote: Vim will run much slower. If your.vimrcis big or you have severalplugins you need to be patient for startup, or run with the "--clean"argument.There are oftena few leaks from libraries, suchas getpwuid() andXtVaAppCreateShell(). Those are unavoidable. The number of bytes should bevery smalla Kbyte or less.==============================================================================3. Windows Bug Reportingdebug-win32If the Windows version of Vim crashes ina reproducible manner, you can takesome steps to providea useful bug report.3.1 GENERICYoumust obtain the debugger symbols (PDB) file for your executable: gvim.pdbfor gvim.exe, or vim.pdb for vim.exe. The PDB should be available from thesame place that you obtained the executable. Be sure to use the PDB thatmatches the EXE (same date).If you built the executable yourself with the MicrosoftVisual C++ compiler,then the PDB was built with the EXE.If you haveVisual Studio, use that instead of the VC Toolkit and WinDbg.For other compilers, you should always use the corresponding debugger:gdb(see abovedebug-gcc) for the Cygwin and MinGW compilers.debug-vs20053.2 Debugging Vim crashes with Visual Studio 2005/Visual C++ 2005 ExpressFirst launch vim.exe or gvim.exe and then launchVisual Studio. (If you don'thaveVisual Studio, follow the instructionsatget-ms-debuggers to obtainafree copy ofVisual C++ 2005 Express Edition.)On the Tools menu, click Attach to Process. Choose the Vim process.In Vim, reproduce the crash.Adialog will appear inVisual Studio, tellingyou about the unhandled exception in the Vim process. Click Break to breakinto the process.Visual Studio will pop up another dialog, telling you that no symbols areloaded and that the source code cannot be displayed. Click OK.Severalwindows will open. Right-click in the Call Stack window. Choose LoadSymbols. The Find Symbolsdialog will open, looking for (g)vim.pdb. Navigateto the directory where you have the PDB file and click Open.At this point, you should havea full call stack with vim function names andline numbers. Double-click one of the lines and the Find Sourcedialog willappear. Navigate to the directory where the Vim sourceis (if you have it.)If you don't know how to debug this any further, follow the instructionsat ":helpbug-reports". Paste the call stack into the bug report.If you havea non-free version ofVisual Studio, you can savea minidump viathe Debug menu and sendit with the bug report.A minidumpisa small file(<100KB), which contains information about the state of your process.Visual C++ 2005 Express Edition cannot save minidumps andit cannot beinstalledasa just-in-time debugger. Use WinDbg,debug-windbg, if youneed to save minidumps or you wanta just-in-time (postmortem) debugger.debug-windbg3.3 Debugging Vim crashes with WinDbgSeeget-ms-debuggers to obtaina copy of WinDbg.As with theVisual Studio IDE, you can attach WinDbg toa running Vim process.You can also have your system automatically invoke WinDbgasa postmortemdebugger. To set WinDbgas your postmortem debugger, run "windbg -I".To attach WinDbg toa running Vim process, launch WinDbg. On the File menu,choose Attach toa Process.Select the Vim process and click OK.At this point, choose Symbol File Path on the File menu, and add the foldercontaining your Vim PDB to the sympath. If you have Vim source available,use Source File Path on the File menu. You can now open source files in WinDbgand set breakpoints, if you like. Reproduce your crash. WinDbg should open thesource fileat the point of the crash. Using theView menu, you can examinethe call stack, local variables, watch windows, and so on.If WinDbgis your postmortem debugger, youdo not need to attach WinDbg toyour Vim process. Simply reproduce the crash and WinDbg will launchautomatically. As above, set the Symbol File Path and the Source File Path.To savea minidump, type the followingat the WinDbg command line: .dump vim.dmpdebug-minidump3.4 Opening a MinidumpIf you havea minidump file, you can openit inVisual Studio or in WinDbg.InVisual Studio 2005: on the File menu, choose Open, then Project/Solution.Navigate to the .dmp file and open it. Now press F5 to invoke the debugger.Follow the instructions indebug-vs2005 to set the Symbol File Path.In WinDbg: choose Open Crash Dump on the File menu. Follow the instructions indebug-windbg to set the Symbol File Path.get-ms-debuggers3.5 Obtaining Microsoft Debugging ToolsThe Debugging Tools for Windows (including WinDbg) can be downloaded fromhttps://learn.microsoft.com/en-us/windows-hardware/drivers/debugger/debugger-download-toolsThis includes the WinDbg debugger.Visual C++ 2005 Express Edition can be downloaded for free from:http://msdn.microsoft.com/vstudio/express/visualC/default.aspx========================================================================= vim:tw=78:ts=8:noet:ft=help:norl: