#pragma warn example in C

-


For disabling warnings (non-critical Messages ) we can use #pragma warn directive


Syntax:

 #pragma warn +xxx
#pragma warn -xxx
#pragma warn .xxx

 + -----> means on
- -----> means off
. ------> means toggle

 xxx is  a 3 character warning code. For example rvl means ignore all the warnings where there is function which has to  return value but is not returning.

 Code:
#include<stdio.h>

 #pragma warn rvl
int add(int a,int b);
int main()
{

add(3,5);

}


int add(int a,int b){
printf("The result is %d",a+b);
}

This will not be supported by gcc  compiler as it does not support all the #pragma directives . First if we compile this program with gcc ,the compiler will not show any warnings. To see the warnings we have to pass -Wall arguments to the gcc compiler. 

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