compile and install bugs on irix

[Jerry James]

Jeffrey A Law <law@cygnus.com> wrote:
> What symbols does libz reference from libCsup?  I don't see anything that
> shouldn't be defined by the C library when I look at libz on our irix6.5
> system.

Apparently, Stephane and Alexandre have the same situation on their 6.3
installations that I have on my 6.2 installation; namely,
/usr/lib/libz.so is actually a soft link to /usr/lib/libiflPNG.so.
Here's what happens when I compile a small program that uses the
compression library.

% gcc minigzip.c -o minigzip -lz
ld32: WARNING 85: definition of __TID_11iflColormap in /usr/lib32/libz.so preempts that definition in /usr/lib32/libifl.so.
ld32: WARNING 85: definition of __TID_11iflListItem in /usr/lib32/libz.so preempts that definition in /usr/lib32/libifl.so.
ld32: WARNING 85: definition of __TID_9iflFormat in /usr/lib32/libz.so preempts that definition in /usr/lib32/libifl.so.
% ./minigzip
 4430:./minigzip: rld: Error: unresolvable symbol in /usr/lib32/libiflPNG.so: __pure_virtual_called
 4430:./minigzip: rld: Error: unresolvable symbol in /usr/lib32/libiflPNG.so: __vtbl__9type_info
 4430:./minigzip: rld: Error: unresolvable symbol in /usr/lib32/libifl.so: __vtbl__9type_info
 4430:./minigzip: rld: Error: unresolvable symbol in /usr/lib32/libifl.so: __pure_virtual_called
 4430:./minigzip: rld: Fatal Error: this executable has unresolvable symbols

When I add "-lCsup" to the end of the compile line, it works fine.

> Before I make any changes, I want to know why the irix6.5 box I've got access
> to does not fail.

That suggests that SGI broke the libz stuff out of libiflPNG for 6.5,
thereby avoiding the problem as far as egcs is concerned.
Unfortunately, for earlier versions of Irix, if you're going to use -lz
at all, then you'll also have to check whether -lCsup is needed.  (It
won't be for those who have compiled libz from sources.)
-- 
Jerry James
Email: jerry@cs.ucsb.edu
WWW:   http://www.cs.ucsb.edu/~jerry/