thisisnic commented on a change in pull request #11658:
URL: https://github.com/apache/arrow/pull/11658#discussion_r747498927
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File path: r/vignettes/developers/debugger.Rmd
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+# Running R code with the C++ debugger
+
+As Arrow has C++ code at its core, debugging code can sometimes be tricky when
+errors originate in the C++ rather than the R layer. If you are adding new
code
+which triggers a C++ bug (or find one in existing code), this can result in a
+segfault. If you are working in RStudio, the session is aborted, and you may
+not be able to retrieve the error messaging needed to diagnose and/or report
+the bug. One way around this is to find the code that causes the error, and
+run R with a C++ debugger.
+
+Firstly, load R with your debugger. The most common debuggers are `gdb` and
`lldb`
+
+In my case it's `gdb`, but if you're using the `lldb` debugger, just swap in
+that command here.
+
+```shell
+R -d gdb
+```
+
+Next, run R.
+
+```shell
+run
+```
+
+You should now be in an R session with the C++ debugger attached. This will
+look similar to a normal R session, but with extra output. For example, here
+is the output I get from running an R session in the debugger
+and then loading arrow:
+
+```
+R version 4.1.1 (2021-08-10) -- "Kick Things"
+Copyright (C) 2021 The R Foundation for Statistical Computing
+Platform: x86_64-pc-linux-gnu (64-bit)
+
+R is free software and comes with ABSOLUTELY NO WARRANTY.
+You are welcome to redistribute it under certain conditions.
+Type 'license()' or 'licence()' for distribution details.
+
+ Natural language support but running in an English locale
+
+R is a collaborative project with many contributors.
+Type 'contributors()' for more information and
+'citation()' on how to cite R or R packages in publications.
+
+Type 'demo()' for some demos, 'help()' for on-line help, or
+'help.start()' for an HTML browser interface to help.
+Type 'q()' to quit R.
+
+[Detaching after vfork from child process 48943]
+[Detaching after vfork from child process 48945]
+> library(arrow)
+[New Thread 0x7ffff326d700 (LWP 48953)]
+[New Thread 0x7fffeb7ff700 (LWP 48958)]
+
+Attaching package: ‘arrow’
+
+The following object is masked from ‘package:utils’:
+
+ timestamp
+```
+
+Now, run your code - either directly in the session or by sourcing it from a
+file. If the code results in a segfault, you will have extra output that you
+can use to diagnose the problem or attach to an issue as extra information.
Review comment:
Have added a few bits including equivalent gdb and lldb commands now.
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