In computer science, pointer analysis, or points-to analysis, is a static code analysis technique that establishes which pointers, or heap references, can point to which variables, or storage locations. It is often a component of more complex analyses such as escape analysis. A closely related technique is shape analysis.

This is the most common colloquial use of the term. A secondary use has pointer analysis be the collective name for both points-to analysis, defined as above, and alias analysis. Points-to and alias analysis are closely related but not always equivalent problems.

Consider the following C program:

A pointer analysis computes a mapping from pointer expressions to a set of allocation sites of objects they may point to. For the above program, an idealized, fully precise analysis would compute the following results:

(Where X::Y represents the stack allocation holding the local variable Y in the function X.)

However, a context-insensitive analysis such as Andersen's or Steensgaard's algorithm would lose precision when analyzing the calls to id, and compute the following result:

As a form of static analysis, fully precise pointer analysis can be shown to be undecidable. Most approaches are sound, but range widely in performance and precision. Many design decisions impact both the precision and performance of an analysis; often (but not always) lower precision yields higher performance. These choices include:

Pointer analysis algorithms are used to convert collected raw pointer usages (assignments of one pointer to another or assigning a pointer to point to another one) to a useful graph of what each pointer can point to.