What were you trying to do that didn't work?

I was trying to debug a C++ library with the system tools (not a toolset).

GDB only showed me the raw data for an STL container instead of the pretty-printed ones.

A quick test with a 5 line program shows that it worked fine in that setting.

My actual setting is a swig-wrapped c++ library.  I'm importing the library into python and stopping in the C++ code.  The pretty-printers were missing there.

One more observation: if I start gdb on a simple test program and enter `info pretty-printers` before running the program, the pretty-printers aren't loaded.  They do appear to be loaded after the program starts running. 

Is it possible that the hook to load the pretty-printers isn't triggered when the main debugged program is python instead of c++?

Please provide the package NVR for which bug is seen:

(watnlp) [jlquinn@bertdev01 engines]$ rpm -q gdb

gdb-8.2-20.el8.x86_64

How reproducible:

It showed up for me debugging a python package swig-wrapped c++ library.  I had to manually import the pretty printers in .gdbinit.

But it works fine with a standard c++ program on the command line.

If I add the following to .gdbinit, then I get the pretty printers within the swig c++ library too:

python
import sys
sys.path.insert(0, '/usr/share/gcc-8/python')
from libstdcxx.v6.printers import register_libstdcxx_printers
register_libstdcxx_printers (None)
end

Steps to reproduce

1. Create a swig-wrapped c++ library
2. Import into a conda python (I used 3.10.13)
3. Run the python script in gdb
4. break in the c++ library
5. in gdb, print a vector<float>

Expected results

(gdb) p x
$1 = std::vector of length 5, capacity 5 = {1, 2, 3, 4, 5}

Actual results

(gdb) p/r x
$2 = {<std::Vector_base<float, std::allocator<float> >> = {_M_impl = {<std::allocator<float>> = {<_gnu_cxx::new_allocator<float>> =

, <No data fields>}, 
      _M_start = 0x613eb0, _M_finish = 0x613ec4, _M_end_of_storage = 0x613ec4}}, <No data fields>}

I used p/r here to duplicate it in a quick 5 line program.