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Do not cast away a const qualification on a variable type.  Casting away the const qualification will allow violation of rule \[[EXP31-C|EXP31-C. Do not modify constant values ]\] prohibiting the modification of constant values.

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Otherwise, do not attempt to modify the contents of the array.

Exception

It is acceptable to cast away const when invoking a legacy API that does not accept a const argument provided the function does not attempt to modify the referenced variable. For example, the following code casts away the const-qualification of INVFNAME in the call to the log() function.

void log(char *errstr) {
  fprintf(stderr, "Error: %s.\n", errstr);
}

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const char INVFNAME[]  = "Invalid file name.";
log((char *)INVFNAME);
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Priority: P6 Level: L2

If the object really is constant, the compiler may have put it in ROM or write-protected memory. Trying to modify such an object may lead to a program crash. This could allow an attacker to mount a denial of service attack.

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