[Bug libstdc++/30416] New: SIGSEGV in valarray::cshift(n) on empty array

["sebor at roguewave dot com" <gcc-bugzilla at gcc dot gnu dot org>]

AFAIK, the program below should have well-defined behavior but it abends with
gcc 4.1.0 on Solaris 9.

$ cat t.cpp && g++ -g t.cpp -static && gdb ./a.out
#include <valarray>

int main ()
{
    const std::valarray<int> a;

    a.cshift (1);
} 
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This GDB was configured as "sparc-sun-solaris2.9"...
(gdb) run
Starting program: a.out 

Program received signal SIGSEGV, Segmentation fault.
0x00024db8 in memcpy ()
(gdb) where
#0  0x00024db8 in memcpy ()
#1  0x00010368 in std::_Array_copy_ctor<int, true>::_S_do_it (__b=0x0, 
    __e=0x4, __o=0xffbffb94)
    at
/usr/local/gcc-4.1.0/lib/gcc/sparc-sun-solaris2.9/4.1.0/../../../../include/c++/4.1.0/bits/valarray_array.h:165
#2  0x00010398 in std::__valarray_copy_construct<int> (__b=0x0, __e=0x4, 
    __o=0xffbffb94)
    at
/usr/local/gcc-4.1.0/lib/gcc/sparc-sun-solaris2.9/4.1.0/../../../../include/c++/4.1.0/bits/valarray_array.h:174
#3  0x0001057c in std::valarray<int>::cshift (this=0xffbffc20, __n=1)
    at
/usr/local/gcc-4.1.0/lib/gcc/sparc-sun-solaris2.9/4.1.0/../../../../include/c++/4.1.0/valarray:821
#4  0x00010288 in main () at /nfs/b20/sebor/tmp/t.cpp:8


-- 
           Summary: SIGSEGV in valarray::cshift(n) on empty array
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: sebor at roguewave dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30416