rspec/rules/S936/rule.adoc

Using a "bald" function name is likely a bug. Rather than testing the return value of a function with a ``void`` parameter list, it implicitly retrieves the address of that function in memory. If that's truly what's intended, then it should be made explicit with the use of the ``&`` (address-of) operator. If it's not, then a parameter list (even an empty one) should be added after the function name.


== Noncompliant Code Example

----
int func(void) {
  // ...
}

void f2(int a, int b) {
  // ...
  if (func) {  // Noncompliant - tests that the memory address of func() is non-null
    //...
  }
  // ...
}
----


== Compliant Solution

----
void f2(int a, int b) {
  // ...
  if (func()) {  // tests that the return value of func() > 0
    //...
  }
  // ...
}
----


== Exceptions

Callback functions are a common occurrence and are usually not passed with a preceding &. There is however little ambiguity so this rule ignores function identifiers when used as a parameter of a function call.

----
void foo() {
  // ...
}

registerEvent(AnEvent, foo);
----


== See

* MISRA C:2004, 16.9 - A function identifier shall only be used with either a preceding &, or with a parenthesized parameter list, which may be empty.
* MISRA C++:2008, 8-4-4 - A function identifier shall only be used to call the function or it shall be preceded by &.