MEM86-C. Use a Goto-Chain when leaving a function on error after allocating multiple objects

Many functions require the allocation of multiple objects.  Failing and returning somewhere in the middle of this function without freeing all of the allocated memory could produce a memory leak.  It is a common error to forget to free one (or all) of the objects in this manner, so a goto-chain is the simplest and cleanest way to organize exits when order is preserved.

Noncompliant Code Exampleint do_something(void){

// ... definitions ,,,

obj1 = malloc(...);
if (!obj1)

obj2 = malloc(...);
if (!obj2)

obj3 = malloc(...);
if (!obj3)

// ... more code ...
}

Compliant Solutionint do_something(void){

// ... definitions ,,,

obj1 = malloc(...);
if (!obj1)

obj2 = malloc(...);
if (!obj2)

obj3 = malloc(...);
if (!obj3)

// ... more code ...

FAIL_OBJ3:
free(obj2);

FAIL_OBJ2:
free(obj1);

FAIL_OBJ1:
return -1;
}

This code is guaranteed to clean up properly whenever an allocation fails.  It is cleaner and prevents rewriting of similar code upon every function error.