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Subj:	I want to call a struct-valued library function on a sparc.

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Date: 18 Mar 91 22:58:01 GMT
From: netnews!mjd@noc2.dccs.upenn.edu  (Mark-Jason Dominus)
Organization: University of Pennsylvania
Subject: I want to call a struct-valued library function on a sparc.
Message-Id: <MJD.91Mar18175801@saul.cis.upenn.edu>
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To: help-gcc@prep.ai.mit.edu


Sun has a library called `ndbm' which provides fast hashed database
storage and access.  Some of the routines (e.g., `dbm_firstkey()',
`dbm_nextkey()') return a struct { char *dptr; int dsize; } ;

My gcc-compiled calling routine doesn't get the right structure returned
from these routines, either with or without -fpcc-struct-return.  The
GCC info file (node `Incompatibilities') says:

     On the Sparc, GNU CC uses an incompatible calling convention for
     structures.  It passes them by including their contents in the
     argument list, whereas the standard compiler passes them
     effectively by reference.

     This really ought to be fixed, but such calling conventions are
     not yet supported in GNU CC, so it isn't straightforward to fix
     it.

     The convention for structure returning is also incompatible, and
     `-fpcc-struct-return' does not help.

Is there a workaround that is better than each of:
	``use another compiler''
	``use another architecture''
	``rewrite the library routine''
?
--

   Nihil tam absurde dici potest, quod non dicatur ab aliquo pilosophorum.
Mark-Jason Dominus 	  			    mjd@central.cis.upenn.edu