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ccastingassignment-operator

Is it possible to cast an 'assignment by operator' operation?

For example:

int a = 10;
float b 1.5;
a*=b; //"warning C4244: '*=' : conversion from 'float' to 'int', possible loss of data"

I want to suppress this warning. Of course, one why is to do so is:

a = (int)(a*b);

So actually I have two question:

  1. Is there a way to keep using the assignment by operator and casting it in between?
  2. Is there a way I can suppress the warning w/o using casting?
Solution

  • Is there a way to keep using the assignment by operator and casting it in between?

    No. Anything on the RHS of a *= b affects b and not the product a*b.

    Is there a way I can suppress the warning w/o using casting?

    Use a nearest integer function that handles the conversion. The 2 functions below round to nearest rather than truncate as in some_int = some_float.

    #include <math.h>

// long int lrintf(float x); 
// round their argument to the nearest integer value
// rounding according to the current rounding direction.
int a = 10;
float b = 1.5;
a = lrintf(a * b);

// or

// long int lroundf(float x);
// The lround and llround functions round their argument to the nearest integer value, 
// rounding halfway cases away from zero, regardless of the current rounding direction.