[PPL-devel] if the compiler has the remainder bug... yes ??

[Roberto Bagnara]

On 12/11/10 00:07, Dennis Clarke wrote:
>
> Could someone explain what this "remainder bug" is ?
>
> .
> .
> .
> checking the binary format of C++ long doubles... IEEE754 Quad Precision
> checking whether C++ provides exact output for long doubles... no
> checking whether the C++ compiler supports flexible arrays... yes
> checking whether the IEEE inexact flag is supported in C++... no
> checking if the compiler has the remainder bug... yes
> checking whether the C++ compiler supports __attribute__ ((weak))... yes
> checking for fenv.h... (cached) yes
> checking for ieeefp.h... (cached) yes
> checking getopt.h usability... no
> checking getopt.h presence... no
> checking for getopt.h... no
> .
> .
> .

It is a bug whereby the compiler miscompiles the remainder expression
in a way that causes INT_MIN % -1 to yield  a SIGFPE on CPUs of the
i386 family.

-- 
Prof. Roberto Bagnara
Applied Formal Methods Laboratory
Department of Mathematics, University of Parma, Italy
http://www.cs.unipr.it/~bagnara/
mailto:bagnara at cs.unipr.it