  Malformed data-structures can lead to runtime errors such as arbitrary memory
access or corruption. Despite this, reasoning over data-structure properties
for low-level heap manipulating programs remains challenging. In this paper we
present a constraint-based program analysis that checks data-structure
integrity, w.r.t. given target data-structure properties, as the heap is
manipulated by the program. Our approach is to automatically generate a solver
for properties using the type definitions from the target program. The
generated solver is implemented using a Constraint Handling Rules (CHR)
extension of built-in heap, integer and equality solvers. A key property of our
program analysis is that the target data-structure properties are shape
neutral, i.e., the analysis does not check for properties relating to a given
data-structure graph shape, such as doubly-linked-lists versus trees.
Nevertheless, the analysis can detect errors in a wide range of data-structure
manipulating programs, including those that use lists, trees, DAGs, graphs,
etc. We present an implementation that uses the Satisfiability Modulo
Constraint Handling Rules (SMCHR) system. Experimental results show that our
approach works well for real-world C programs.
