Problem scenario
You compile a C program (with gcc foobar.cc) but you get an error message like this:
"foofbar1.cc:71...: warning: format '%s' expects argument of type 'char*', but argument 2 has type 'int' [-Wformat=]
printf ("y is a %s\n", y);
^ "
What do you do to not get this error?
Solution
While the code compiles, the executable may not run. A compilation error can be benign. For this case, integers need a special syntax to be printed out.
Here is a line that will produce this error (with a variable named "y"):
printf ("y is a %s\n", y);
Here is a similar but corrected line that will be error free:
printf ("y is a %d\n",y);
The "%s" is appropriate for printing string variables. For integer variables, use "%d" syntax.
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