After I run python3 (to run the REPL) and type "r" and then PgUp twice, I get a segfault. I'm on Mageia Linux x86-64 6 , but recall a similar problem happening before:

shlomif@telaviv1:~$ python3
Python 3.4.3 (default, Aug 13 2015, 21:40:54) 
[GCC 4.9.2] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> rSegmentation fault
shlomif@telaviv1:~$ python3^C

I'm attaching the /etc/inputrc.

What makes you think this is a bug in Python?  Can you reduce the inputrc to the minimum that reproduces the problem?

Sorry, should have been clearer "a bug in python as opposed to one in Mageia's readline".

I'm attaching here the reduced, minimal, inputrc. I think it's a bug in Python because it doesn't happen with any other program that uses readline (bash, perl -d, etc.) that I checked. I'll check with a vanilla readline compiled from source from the GNU site , though.

I can't reproduce it on my Gentoo box using 3.4 tip.

Maybe the problem is using escape characters (0x1b) instead of \e. Try using the following:

"\e[5~": history-search-backward

FWIW, your inputrc doesn't crash my system (64-bit Linux, readline 6.3 and Python 3.4).

Hi all!

Thanks for the investigation.

I have now built readline-6.3 from source using:

./configure --prefix="$HOME/apps/readline-TO_DEL" --with-curses=yes --enable-multibyte

and installed it. Then I built python 3.4.3 from source against it by setting LIBRARY_PATH/CPATH/etc. and by this patch to setup.py:

        if True: # if cross_compiling:
            self.add_gcc_paths()

After I built it and ran it, it still segfaults after I type "r" and press PgUp twice. I've attached the strace output (compressed with xz).

A gdb backtrace may be of more help than strace.

gdb by full attached.

Well it looks like you’ve identified that PgUp triggers a history search. Perhaps it would be good to look at your /home/shlomif/.python_history file, assuming there is nothing sensitive in there. The strace output only indicates it is 411 bytes and gives the first one-and-a-half lines. My guess is there is something funny about a line beginning with “r”, or a nearby line.

But it still sounds like a Readline bug instead of a Python bug. If you clear or remove the history file, does the bug go away? Maybe you can replace the equivalent ~/.bash_history or Perl history file to see if it triggers a crash there.

According to the GDB backtrace, _rl_kscxt is a null pointer at <https://github.com/Distrotech/readline/blob/readline-6.3/callback.c#L188>, while the _rl_dispatch_callback() function doesn’t handle null pointers. Maybe you would find the Readline people more knowledgeable about this.

Marting Panter: I'm getting the same problem with a completely empty ~/.python_history file. Moreover, I was able to reproduce a similar bug in gdb. I'll try seeing if I can create a minimal GNU readline-using program here that reproduces it.

Martin: [sorry for misspelling your name] I was now able to reproduce the same problem using rlwrap (see http://utopia.knoware.nl/~hlub/rlwrap/ ). I'll report it to the readline problem.