char *

 why the following compile is OK

but will crash when execute?

the problem seem to in -
convertToUppercase( phrase );

==========
// Converting lowercase letters to uppercase letters
// using a non-constant pointer to non-constant data.
#include <iostream>
using std::cout;
using std::endl;

#include <cctype> // prototypes for islower and toupper
using std::islower;
using std::toupper;

void convertToUppercase( char * );

int main()
{
   //char phrase[] = "characters and $32.98";

   char * phrase = "characters and $32.98";

   convertToUppercase( phrase );

   return 0; // indicates successful termination
} // end main

// convert string to uppercase letters
void convertToUppercase( char *sPtr )
{
   while ( *sPtr != '\0' ) // loop while current character is not '\0'
   {
      if ( islower( *sPtr ) ) // if character is lowercase,
         *sPtr = toupper( *sPtr ); // convert to uppercase

      sPtr++; // move sPtr to next character in string
   } // end while
} // end function convertToUppercase