SA0090: POUs shall have a single point of exit

Detects code locations where the RETURN statement is not the last statement in a function, method, property, or program. Locations where a RETURN exists within an IF branch are also detected.

Justification: A RETURN in the code results in worse maintainability, testability, and readability of the code. A RETURN in the code is easily overlooked. Before each RETURN, it is often forgotten to insert code that should always be executed when exiting a function.

Importance: Medium

PLCopen rule: CP14

FUNCTION SA0090: DINT
VAR_INPUT
    bTest : BOOL;
END_VAR

IF bTest THEN
    RETURN;
END_IF
SA0090 := 99;