Pretty Printers

[georglauterbach]

I have a question about pretty printers. When I want to list them, gdb tells me this:

(gdb) info pretty-printer
Undefined info command: "pretty-printer".  Try "help info"

Does this project not support pretty printers? I think I am a bit confused :)

[guyush1]

Hello @georglauterbach

This command indeed does not work. I investigated a little, and found out something very interesting:

As you can see, if i manually import the module, the command appears.
I think i know how to properly solve this - i just need to import this module at the init.py of the gdb python module. This usually happens by the auto-load feature of gdb, but since we are static-linking - we are not using auto-load.

@roddyrap what do you think?

[guyush1]

We might also want to freeze the pretty printers present at /user/share/gdb

[roddyrap]

I modified the gdb initialization module to do less things than usual because it looks for files which aren't available when using a static version.

I may have been over enthusiastic though, so I will look into initializing everything that is possible to initialize.

Will update soon.

[georglauterbach]

Thank you very much!

I was also able to use the workaround via Python:

import pathlib
import sys

module_path = pathlib.Path(<SOME MODULE PATH>)
if module_path.exists():
  sys.path.insert(0, str(module_path))

  import gdb.command.pretty_printers # type: ignore

  from libstdcxx.v6.printers import register_libstdcxx_printers # type: ignore
  register_libstdcxx_printers(None)

[guyush1]

@roddyrap please work above my #38 as it contains some changes to gdb's python api as well

[roddyrap]

I found the problem, and my guess was right. The imports are just not being made during the initialization.

I am working on it right now, so hopefully a fix will be available soon.

[borjamunozf]

Hi :) first of all, thanks a lot for this effort! This was a nightmare for a while and I spent too much time linking statically the latest gdb versions.

Can confirm that this does not work (vscode). I tried to add or enforce registering pp in the .gdbinit

-> R (launch-2): {"type":"response","request_seq":2,"success":false,"command":"launch","message":"Unable to start debugging. Unexpected GDB output from command \"-interpreter-exec console \"source ~/.gdb/.gdbinit\"\". ~/.gdb/.gdbinit:6: Error in sourced command file:\nScripting in the \"Python\" language is not supported in this copy of GDB.","body":{"error":{"id":1005,"format":"Unable to start debugging. Unexpected GDB output from command \"-interpreter-exec console \"source ~/.gdb/.gdbinit\"\". ~/.gdb/.gdbinit:6: Error in sourced command file:\nScripting in the \"Python\" language is not supported in this copy of GDB."

cat .gdbinit
python
import sys
sys.path.insert(0, '/usr/share/gcc/python/')
from libstdcxx.v6.printers import register_libstdcxx_printers
register_libstdcxx_printers (None)
end
```

[georglauterbach]

Hi :) first of all, thanks a lot for this effort! This was a nightmare for a while and I spent too much time linking statically the latest gdb versions.

Can confirm that this does not work (vscode). I tried to add or enforce registering pp in the .gdbinit

-> R (launch-2): {"type":"response","request_seq":2,"success":false,"command":"launch","message":"Unable to start debugging. Unexpected GDB output from command \"-interpreter-exec console \"source ~/.gdb/.gdbinit\"\". ~/.gdb/.gdbinit:6: Error in sourced command file:\nScripting in the \"Python\" language is not supported in this copy of GDB.","body":{"error":{"id":1005,"format":"Unable to start debugging. Unexpected GDB output from command \"-interpreter-exec console \"source ~/.gdb/.gdbinit\"\". ~/.gdb/.gdbinit:6: Error in sourced command file:\nScripting in the \"Python\" language is not supported in this copy of GDB."

cat .gdbinit
python
import sys
sys.path.insert(0, '/usr/share/gcc/python/')
from libstdcxx.v6.printers import register_libstdcxx_printers
register_libstdcxx_printers (None)
end

Did you use the correct package? This project provides a version with and without python - did you accidentally choose the latter?

[roddyrap]

Prepared the fix. Hopefully, at least @guyush1 will check it, and then we'll merge it with the GDB 16 update.

The next version should be good.