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libstdc++/9679: Strange behaviour of valarray::apply method
- From: dens at stl dot sarov dot ru
- To: gcc-gnats at gcc dot gnu dot org
- Date: 12 Feb 2003 22:14:33 -0000
- Subject: libstdc++/9679: Strange behaviour of valarray::apply method
- Reply-to: dens at stl dot sarov dot ru
>Number: 9679
>Category: libstdc++
>Synopsis: Strange behaviour of valarray::apply method
>Confidential: no
>Severity: serious
>Priority: medium
>Responsible: unassigned
>State: open
>Class: sw-bug
>Submitter-Id: net
>Arrival-Date: Wed Feb 12 22:16:00 UTC 2003
>Closed-Date:
>Last-Modified:
>Originator: dens@stl.sarov.ru
>Release: libstdc++-3.2-7
>Organization:
>Environment:
cat /etc/issue
Red Hat Linux release 8.0 (Psyche)
Kernel \r on an \m
g++ --version
g++ (GCC) 3.2 20020903 (Red Hat Linux 8.0 3.2-7)
>Description:
There is very strange(for me) behaviour of apply method of valarray:
#include <valarray>
#include <string.h>
char bar(char arg)
{
return tolower(arg);
}
char foo(char * x)
{
return toupper(*x);
}
int main(void)
{
char * str = new char[7];
strcpy(str,"STRING");
std::valarray<char> y(str, 6);
/// Strange behaviour
char some = foo(&(y.apply(bar)[0]));
return 0;
}
If I understood correctly then apply method should return valarray<char> object which operator [] should return reference to char (char &). (C++ standard 26.3.2.3 and 26.3.2.7 8.)
But in our case this operator returns non-lvalue and I can't get it address. It is very strange for me.
>How-To-Repeat:
Try to compile attached sample
>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted:
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