The configure script checks for various library calls
just by calling them prefixed with (void), thus
verifying they exist but not checking if their type is
correctly declared.
On Irix and MIPSPro cc, various _r functions
(ctermid_r, gethostbyaddr_r etc) need extra directives
in order to be declared.  This is what the patch does.
Note: in the patch, the check against the CC var is
"cc*)" and not "cc)".  This is deliberate, because if
there is a SGI_ABI env var set to something (eg. -64
for 64bit executable), the configure script changes the
CC var to include the SGI_ABI contents.

Logged In: YES 
user_id=21627

Can you please add a comment (in the patch) which of these
defines is necessary to activate what specific feature?

Five years from now, the need for these defines may be gone,
but nobody will dare to remove the defines since nobod knows
why they are there in the first place.

Also, what versions of Irix has this patch been tested on?
Which additional versions is it supposed to work on?

Logged In: YES 
user_id=539787

These defines apply for the compiler MIPSPro 7.x.
Since it is cumbersome to make that clear in the configure
script, I chose to make patches directly to the three
modules that failed to compile, where it's easiest to check
for OS and compiler version.
The three modules are _hotshot, posixmodule and
socketmodule.
The patch has been tested on Irix 6.5 (I have no access to
older versions) and on three separate machines (Indy, Octane
and an Origin2K), and that is why I was a little slow in
replying.
Please delete the previous patch (if you have permission
to).

Logged In: YES 
user_id=21627

The patch looks good, but I still must request a summary
comment above each of the changes that indicates what
compilation or runtime changes are fixed.

Logged In: YES 
user_id=539787

Inserted the comments requested.

Logged In: YES 
user_id=21627

Thanks for the patch. Committed as 

_hotshot.c 1.29;
posixmodule.c 2.260;
socketmodule.c 1.245;