[cfe-dev] New division by zero check

[Anders Rönnholm]

Hi,



There is a division by zero check where the denominator value is already known. I would like some feedback on a new static check for division by zero I intend to write where the value isn't known yet.



It shall catch scenarios where the division is made before checking it against a value. To start with it will have to be directly after the division.



e.g

x = 100 / y;

if (y == 0)



I plan to do it by:


1. When a division is reached where the denominator is a variable with unknown value, "mark" the denominator variable.
2. When reaching a condition that checks if a variable is 0, check if the variable in the condition is "marked".
3. Report bug



I guess RecursiveASTVisitor is best for this?

Is there perhaps a better way to do this that would allow me to follow the variable from division to check so that  it doesn't have to be directly after?

//Anders

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