[Bug c++/28981] New: g++ -pedantic issues error array bound not integer although it is a constant

[brase at lucent dot com]

g++ version: 4.1.1
target platform: linux kernel 2.6.13-15

with option "pedantic" the following line does not compile outside main:

int array3[(const unsigned short) (20.5 * 3)];

error message from compiler is:
"error: array bound is not an integer constant"

to me this is wrong because the expression "(const unsigned short) (20.5 * 3)"
is an integer constant

Note: within main the same expression does compile with pedantic option

Here is a sample program:
// Begin of sample program
//
// Question: Why does array3 not compile ?
// this file demonstrates a problem in compilation with the pedantic option
//
// btspc21  > g++ -pedantic -c compiler_fail.cc
// compiler_fail.cc:18: error: array bound is not an integer constant


// float conversion alone compiles

int array1[(const unsigned short) (20.5)];

// calculation compiles

int array2[(const unsigned short) (20 * 45)];

// combination does not compile

int array3[(const unsigned short) (20.5 * 3)];

int main()
{
    // combination in main does compile

    int array4[(unsigned short) (20.5*3)];
}

// End of sample program


-- 
           Summary: g++ -pedantic issues error array bound not integer
                    although it is a constant
           Product: gcc
           Version: 4.1.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: brase at lucent dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28981