Static Analysis Methods for Finding Errors in Code — Part 1

Static analysis is a powerful technique for finding errors in code. By analyzing the code without executing it, static analysis tools can identify a wide range of issues, from simple syntax errors to complex security vulnerabilities. In this post, we’ll explore five methods used in static analysis: data flow analysis, control flow analysis, taint analysis, symbolic execution, and abstract interpretation.

Data Flow Analysis

Data flow analysis is a technique for tracking how data moves through a program. It involves analyzing the definitions and uses of variables, as well as the control flow of the program. Data flow analysis can be used to identify a variety of issues, such as uninitialized variables, null pointer dereferences, and data races.

For example, consider the following code:

int foo(int a) {
    int b;
    if (a > 0) {
        b = 1;
    }
    return b;
}

A data flow analysis tool would identify that the variable b is not initialized on all paths through the function, and would flag this as a potential error.

Control Flow Analysis

Control flow analysis is a technique for analyzing the paths that a program can take during execution. It involves constructing a control flow graph, which represents the possible paths through the program, and analyzing the graph to identify potential issues.