«

Hi

I am getting the warning below.

************************************************** **************
cd ~/toy/
make -k
g++ -gdwarf-2 -c -o my.o my.cpp
my.cpp: In function ‘int main()’:
my.cpp:7: warning: converting to ‘int’ from ‘double’
g++ -Wall -gdwarf-2 -o proj my.o -lboost_filesystem -lboost_thread -L.

Compilation finished at Mon Jan 29 08:03:34
************************************************** **************

the code is

************************************************** **************
#include <iostream>
using namespace std;

int main(){
double b = 0.04;
int a;
a *= b;
cout << a << endl;
}
************************************************** **************

do I leave the compiler to do the conversion or should I
static_cast<double> (a) before a *= b?
then
static_cast<int> (a) again when finished?

too much work...

thanks

Gary Wessle wrote:
> Hi
>
> I am getting the warning below.
>
> ************************************************** **************
> cd ~/toy/
> make -k
> g++ -gdwarf-2 -c -o my.o my.cpp
> my.cpp: In function ‘int main()’:
> my.cpp:7: warning: converting to ‘int’ from ‘double’
> g++ -Wall -gdwarf-2 -o proj my.o -lboost_filesystem -lboost_thread -L.
> ************************************************** **************
> #include <iostream>
> using namespace std;
>
> int main(){
> double b = 0.04;
> int a;
> a *= b;
> cout << a << endl;
> }
> ************************************************** **************
>
> do I leave the compiler to do the conversion or should I
> static_cast<double> (a) before a *= b?
> then
> static_cast<int> (a) again when finished?
>
The result of the expression a*b will be double, which is implicitly
converted to int on assignment.

Casting won't change that, it'll just hide the compiler warning.

--
Ian Collins.

On Jan 28, 1:08 pm, Gary Wessle <phd...@yahoo.com> wrote:

> #include <iostream>
> using namespace std;
>
> int main(){
> double b = 0.04;
> int a;
> a *= b;
> cout << a << endl;}******************************************** ********************
>
> do I leave the compiler to do the conversion or should I
> static_cast<double> (a) before a *= b?
> then
> static_cast<int> (a) again when finished?

What are you trying to do? a is not initalized, so your program
produces undefined results. If you give us some reasonable code to
look at, we can probably help.
----
Ivan
http://www.0x4849.net