Path: utzoo!yunexus!telly!attcan!uunet!tut.cis.ohio-state.edu!SFI.SANTAFE.EDU!scp
From: scp@SFI.SANTAFE.EDU ("Stephen C. Pope")
Newsgroups: gnu.g++.bug
Subject: g++-1.34.2 generating bogus sparc assembler code
Message-ID: <8904051749.AA16941@laotse.santafe.edu>
Date: 5 Apr 89 17:49:12 GMT
Article-I.D.: laotse.8904051749.AA16941
Sender: daemon@tut.cis.ohio-state.edu
Distribution: gnu
Organization: GNUs Not Usenet
Lines: 52


While trying to compile Lea's Matrix.4apr code, I ran into
the following problem.  I'm using g++-1.34.2, the Tuesday
afternoon distribution, along with a random patch or two
appearing after that distribution.  All on a Sun4 SunOS4.0.1,
and using the native assembler.

laotse% g++ -v -g -O -fchar-charconst  -I.  -fstrength-reduce -c  TriDiagMat.cc
g++ version 1.34.2
 /usr/local/lib/gcc-cpp -+ -v -I. -undef -D__GNU__ -D__GNUG__ -Dsparc -Dsun -Dunix -D__sparc__ -D__su
n__ -D__unix__ -D__OPTIMIZE__ TriDiagMat.cc /tmp/cca16931.cpp
GNU CPP version 1.34
 /usr/local/lib/gcc-c++ /tmp/cca16931.cpp -quiet -dumpbase TriDiagMat.cc -fchar-charconst -fstrength-
reduce -opt -version -G -o /tmp/cca16931.s
GNU C++ version 1.34.2 (sparc) compiled by GNU C version 1.34.
 as /tmp/cca16931.s -o TriDiagMat.o
as: "/tmp/cca16931.s", line 2169: error: statement syntax
as: "/tmp/cca16931.s", line 2425: error: statement syntax
as: "/tmp/cca16931.s", line 2862: error: statement syntax
as: "/tmp/cca16931.s", line 3312: error: statement syntax
as: "/tmp/cca16931.s", line 3762: error: statement syntax
as: "/tmp/cca16931.s", line 4212: error: statement syntax
as: "/tmp/cca16931.s", line 4662: error: statement syntax
as: "/tmp/cca16931.s", line 5112: error: statement syntax
as: "/tmp/cca16931.s", line 5483: error: statement syntax
as: "/tmp/cca16931.s", line 5651: error: statement syntax
as: "/tmp/cca16931.s", line 5881: error: statement syntax
as: "/tmp/cca16931.s", line 6376: error: statement syntax
as: "/tmp/cca16931.s", line 7109: error: statement syntax

(Investigating *only* the first error above!!!)
After looking at the .s output, I see that intructions of
the form

	mov	[%l1], %o2

are being generated.  The source line generating this is
in TriDiagMat.h:

inline double&  TriDiagMat::ref(int i, int j)
{
  return data[r * (j - i + 1) + j];    // this is the culprit here!
}

which is quite kosher.

All the other errors are due to the generation of similar
mov [%l?],%o? instructions.

Stephen Pope
The Santa Fe Institute
scp@sfi.santafe.edu