Re: middle-end/2827: invalid narrowing during use of double type, arrithametic becomes non-comutative

Re: middle-end/2827: invalid narrowing during use of double type, arrithametic becomes non-comutative

[rodrigc]

Synopsis: invalid narrowing during use of double type, arrithametic becomes non-comutative

State-Changed-From-To: open->closed
State-Changed-By: rodrigc
State-Changed-When: Sat Aug 18 08:42:56 2001
State-Changed-Why:
    gcc 3.0.1 produces the correct output:
    

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view&pr=2827&database=gcc

middle-end/2827: invalid narrowing during use of double type, arrithametic becomes non-comutative

[rcr197]

>Number:         2827
>Category:       middle-end
>Synopsis:       invalid narrowing during use of double type, arrithametic becomes non-comutative
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Tue May 15 09:26:01 PDT 2001
>Closed-Date:
>Last-Modified:
>Originator:     Rob Rescorla
>Release:        gcc version egcs-2.91.66 19990314/Liunx (egcs-1.1.2 release)
>Organization:
>Environment:
Redhat Linux 6.2 PII and PIII Intel,
gcc2.8.1 on sparc-sun-solaris2.6 did not demonstrate this behaviour.
>Description:
GCC appears to narrow double to float precision, desptie all
variables involved in a calculation being cast as double.
(Found attempting numerical integration.)

Alternative front ends (CC and G++) also tried, same results.
>How-To-Repeat:
compile the attached program and run.
N.B. running with optomisation causes both subtractions to
produce bad results.

>Fix:
None, re-writing code to force correct compilation was unsuccessfull.
>Release-Note:
>Audit-Trail:
>Unformatted:
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