c/5681: gcc 3.0.3 produces wrong assembler code

[p dot van-hoof at Queens-Belfast dot AC dot UK (Peter van Hoof)]

>Number:         5681
>Category:       c
>Synopsis:       gcc 3.0.3 produces wrong assembler code
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Wed Feb 13 04:16:00 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     Peter van Hoof
>Release:        3.0.3
>Organization:
Queen's University Belfast
>Environment:
System: Linux archer.pst.qub.ac.uk 2.4.2-2 #1 Sun Apr 8 20:41:30 EDT 2001 i686 unknown
Architecture: i686

	<machine, os, target, libraries (multiple lines)>
host: i686-pc-linux-gnu
build: i686-pc-linux-gnu
target: i686-pc-linux-gnu
configured with: ./configure --prefix=/usr/local/gcc3
>Description:
	The compiler generates wrong assembler code in non-optimized mode,
	but works correctly in optimized mode (-O1, -O2, or -O3).
>How-To-Repeat:

archer.pst.qub.ac.uk> gcc -v -save-temps -ansi -g rtoptdepthinit.c
Reading specs from /usr/local/gcc3/lib/gcc-lib/i686-pc-linux-gnu/3.0.3/specs
Configured with: ../gcc-3.0.3/configure --prefix=/usr/local/gcc3
Thread model: single
gcc version 3.0.3
 /usr/local/gcc3/lib/gcc-lib/i686-pc-linux-gnu/3.0.3/cpp0 -lang-c -std=c89 -v -D__GNUC__=3 -D__GNUC_MINOR__=0 -D__GNUC_PATCHLEVEL__=3 -D__ELF__ -D__unix__ -D__linux__ -D__unix -D__linux -Asystem=posix -D__NO_INLINE__ -D__STDC_HOSTED__=1 -Acpu=i386 -Amachine=i386 -D__i386 -D__i386__ -D__tune_i686__ -D__tune_pentiumpro__ rtoptdepthinit.c rtoptdepthinit.i
GNU CPP version 3.0.3 (cpplib) (i386 Linux/ELF)
ignoring nonexistent directory "/usr/local/gcc3/i686-pc-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/local/include
 /usr/local/gcc3/lib/gcc-lib/i686-pc-linux-gnu/3.0.3/include
 /usr/include
End of search list.
 /usr/local/gcc3/lib/gcc-lib/i686-pc-linux-gnu/3.0.3/cc1 -fpreprocessed rtoptdepthinit.i -quiet -dumpbase rtoptdepthinit.c -ansi -g -ansi -version -o rtoptdepthinit.s
GNU CPP version 3.0.3 (cpplib) (i386 Linux/ELF)
GNU C version 3.0.3 (i686-pc-linux-gnu)
        compiled by GNU C version 3.0.3.
 as --traditional-format -V -Qy -o rtoptdepthinit.o rtoptdepthinit.s
GNU assembler version 2.10.91 (i386-redhat-linux) using BFD version 2.10.91.0.2
 /usr/local/gcc3/lib/gcc-lib/i686-pc-linux-gnu/3.0.3/collect2 -m elf_i386 -dynamic-linker /lib/ld-linux.so.2 /usr/lib/crt1.o /usr/lib/crti.o /usr/local/gcc3/lib/gcc-lib/i686-pc-linux-gnu/3.0.3/crtbegin.o -L/usr/local/gcc3/lib/gcc-lib/i686-pc-linux-gnu/3.0.3 -L/usr/local/gcc3/lib/gcc-lib/i686-pc-linux-gnu/3.0.3/../../.. rtoptdepthinit.o -lgcc -lc -lgcc /usr/local/gcc3/lib/gcc-lib/i686-pc-linux-gnu/3.0.3/crtend.o /usr/lib/crtn.o
archer.pst.qub.ac.uk> a.out
2241 3383
3383 3383
a.out: rtoptdepthinit.c:19: RTOptDepthInit: Assertion `StopCalc.iptnu < rfield.nupper-1' failed.
Abort

The correct output would have been:

archer.pst.qub.ac.uk> gcc -O1 -ansi -g rtoptdepthinit.c
archer.pst.qub.ac.uk> a.out
2241 3383
2241 3383

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`
end

>Fix:
	Apart from using optimized mode, no workaround is known.
>Release-Note:
>Audit-Trail:
>Unformatted:
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 Subject: gcc 3.0.3 produces wrong assembler code
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