Doesn't work on newer Linux

[izahn]

Hmm, now when I try to start emacs in a fresh environment, I just get

emacs: symbol lookup error: emacs: undefined symbol: malloc_set_state, version GLIBC_2.2.5

This happens because malloc_set_state has been removed from glibc:

• The deprecated functions malloc_get_state and malloc_set_state have been
  moved from the core C library into libc_malloc_debug.so. Legacy applications
  that still use these functions will now need to preload libc_malloc_debug.so
  in their environment using the LD_PRELOAD environment variable.

So actually this is not because of a change in conda-forge packaging but because of a change in the host operating system. You can work-around with

export LD_PRELOAD=/usr/lib/libc_malloc_debug.so

(assuming you have /usr/lib/libc_malloc_debug.so on the host OS, adjust as needed).

Originally posted by @izahn in #60 (comment)

[asmeurer]

Is there a fix for this? I guess we should check if emacs 28.2 still has the same problem.

[izahn]

I don't think there is any fix others than the LD_PRELOAD work-around. Long-term this will be fixed by building on a host VM with a more recent glibc but conda-forge has been very conservative in that regard, even sticking with CentOS 6 long past EOL.

[zklaus]

I guess one thing we can do is add a pin on __glibc (IIRC). That won't make it work, but it will prevent the installation of an incompatible package.

[izahn]

It's not all the way incompatible though, the LD_PRELOAD work-around is effective. Maybe we can automate it in the activation script?

[zklaus]

Hm. There is the whereis utility. I don't have a Linux with libc_malloc_debug, but could you try

whereis -b libc_malloc_debug

?

Perhaps that allows us to determine the path needed, which we could put in a wrapper startup script.

Alternatively it might be possible to hack the configure script. Basically, we need to tell it that the present libc doesn't have a "Doug Lea Style" malloc; or we could move to a more modern build platform.

[asmeurer]

Does this help?

$ whereis -b libc_malloc_debug
libc_malloc_debug: /usr/lib/x86_64-linux-gnu/libc_malloc_debug.so

[PythonNut]

I don't have libc_malloc_debug on my system:

❯ whereis -b libc_malloc_debug
libc_malloc_debug:

What are my options for getting emacs working (without root access)?