Re: fortran/8445: optimizer bug?

Re: fortran/8445: optimizer bug?

[toon]

Synopsis: optimizer bug?

Responsible-Changed-From-To: unassigned->toon
Responsible-Changed-By: toon
Responsible-Changed-When: Tue Nov 19 13:25:25 2002
Responsible-Changed-Why:
    Fortran Maintainer.
State-Changed-From-To: open->feedback
State-Changed-By: toon
State-Changed-When: Tue Nov 19 13:25:25 2002
State-Changed-Why:
    Does it make any difference compiling this example with
    g77 -O1 -ffloat-store
    ?

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8445

Re: fortran/8445: optimizer bug?

[toon]

Synopsis: optimizer bug?

State-Changed-From-To: feedback->closed
State-Changed-By: toon
State-Changed-When: Fri Feb 14 21:09:02 2003
State-Changed-Why:
    This is a classical case of x86-ism.
    
    The symptoms are:
    
    1. Comparison of two floating point values, one computed
       and one stored.
    
    2. Works on all architectures except x86.
    
    3. Problem goes away when adding -ffloat-store to
       the compiler options.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8445

fortran/8445: optimizer bug?

[eckmann]

>Number:         8445
>Category:       fortran
>Synopsis:       optimizer bug?
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Nov 03 23:46:01 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     eckmann
>Release:        unknown-1.0
>Organization:
>Environment:

>Description:
changing optimizations from O0 to O1 changes output from 1
to 2 lines. There is no problem on macs. but it appears on RH
with gcc 2.95.2 and 2.95.3 on ix86

>How-To-Repeat:
g77 -O0 bug.f -o bug;bug
--------------------------------------
g77 version 2.95.2 19991024 (release) (from FSF-g77 version 0.5.25 19991024 (release))
Driving: g77 -ffixed-line-length-none -v bug.f -o bug -lg2c -lm
Reading specs from /usr/local/gcc-2.95.2/lib/gcc-lib/i686-pc-linux-gnu/2.95.2/specs
gcc version 2.95.2 19991024 (release)
 /usr/local/gcc-2.95.2/lib/gcc-lib/i686-pc-linux-gnu/2.95.2/f771 bug.f -quiet -dumpbase bug.f -version -fversion -ffixed-line-length-none -o /tmp/cckHiTym.s
GNU F77 version 2.95.2 19991024 (release) (i686-pc-linux-gnu) compiled by GNU C version 2.95.2 19991024 (release).
GNU Fortran Front End version 0.5.25 19991024 (release)
 as -V -Qy -o /tmp/ccAPMuUB.o /tmp/cckHiTym.s
GNU assembler version 2.9.1 (i386-redhat-linux), using BFD version 2.9.1.0.24
 /usr/local/gcc-2.95.2/lib/gcc-lib/i686-pc-linux-gnu/2.95.2/collect2 -m elf_i386 -dynamic-linker /lib/ld-linux.so.2 -o bug /usr/lib/crt1.o /usr/lib/crti.o /usr/local/gcc-2.95.2/lib/gcc-lib/i686-pc-linux-gnu/2.95.2/crtbegin.o -L/usr/local/gcc-2.95.2/lib/gcc-lib/i686-pc-linux-gnu/2.95.2 -L/usr/local/gcc-2.95.2/lib /tmp/ccAPMuUB.o -lg2c -lm -lgcc -lc -lgcc /usr/local/gcc-2.95.2/lib/gcc-lib/i686-pc-linux-gnu/2.95.2/crtend.o /usr/lib/crtn.o
-------------------------
similar on RH72, with gcc-2.95.3
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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