mech_eap fails to build on Debian7

[Dan Breslau]

Reported on moonshot-dev by Alejandro Pérez Méndez :

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Hi,

I'm trying to build Moonshot from source on a Debian 7 environment, using the version from the git repository, and it fails saying that:

acquire_cred.c: In function 'gss_acquire_cred':
acquire_cred.c:55:30: error: incompatible type for argument 2 of 'gssEapAcquireCred'
In file included from gssapiP_eap.h:106:0,
                 from acquire_cred.c:37:
util.h:262:1: note: expected 'gss_const_name_t' but argument is of type 'gss_name_t'
acquire_cred.c:56:1: error: control reaches end of non-void function [-Werror=return-type]
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I've confirmed this on Debian 7.9. The problem is that version 1.10 of the MIT Kerberos library, which is distributed on Debian 7.9, contains three invalid definitions. Luke Howard found the Kerberos patch that fixed this:

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commit 884e040c0478c94585395a03dfbb0bbdee7c5ed4
Author: Greg Hudson <email address hidden>
Date: Mon Feb 11 21:13:15 2013 -0500

    Fix RFC 5587 const pointer typedefs

    gss_const_ctx_id_t, gss_const_cred_id_t, and gss_const_name_t are
    supposed to be const pointers to the appropriate structures, not the
    structures themselves. These are not used by any prototypes yet, and
    no application would have any reason to use them as they are, so it
    should be safe to change them within the public header.

    ticket: 7567 (new)
    target_version: 1.11.1
    tags: pullup
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(Unfortunately, the mech_eap code does use those definitions, hence the build failure.)

[Sam Hartman (hartmans)]

Debian 7 is really really old.
As in old enough that it's no longer really supported by debian.
There's something called long-term support available, which is sort of
supported by the Debian project, but let's be clear... Even given
Debian's long release cycle and conservative nature, Debian 7 has gotten
old enough that Debian isn't supporting it any more.