[Bug c++/55020] New: 4.7.2 allow array init wih non-const argument

[Bug c++/55020] New: 4.7.2 allow array init wih non-const argument

[marktbremen45 at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55020

             Bug #: 55020
           Summary: 4.7.2 allow array init wih non-const argument
    Classification: Unclassified
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: minor
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: marktbremen45@gmail.com


Created attachment 28506
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=28506
g++ -v --version > e.lis 2>&1

int main() {
   int sz = 13; // not a constant expression
   int arr[sz];          // should not compile, but does so
}

compiles, but should not. 
Array even works at runtime  with int arg; cin >> arg; int arr[arg]; !

System: Suse Linux 12.2

g++ -v yields:

"
Es werden eingebaute Spezifikationen verwendet.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/i686-pc-linux-gnu/4.7.2/lto-wrapper
Ziel: i686-pc-linux-gnu
Konfiguriert mit: ../gcc-4.7.2/configure --enable-languages=c++
Thread-Modell: posix
gcc-Version 4.7.2 (GCC) 
"
g++ -v --version : see attachment:

[Bug c++/55020] 4.7.2 allow array init wih non-const argument

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55020

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-10-22 12:34:20 UTC ---
This is a GNU extension and works by design, use -pedantic or -pedantic-errors
to get a diagnostic

f.cc:3:14: warning: ISO C++ forbids variable length array 'arr' [-Wvla]

[Bug c++/55020] 4.7.2 allow array init wih non-const argument

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55020

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-10-22 12:36:04 UTC ---
Documented at http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html

[Bug c++/55020] 4.7.2 allow array init wih non-const argument

[marktbremen45 at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55020

--- Comment #3 from marktbremen45 at gmail dot com 2012-10-22 14:20:39 UTC ---
ok - no bug

thanks for the hint