Generating Data Race Witnesses by an SMT-Based Analysis

DOI: 10.1007/978-3-642-20398-5_23
Source: DBLP

ABSTRACT Data race is one of the most dangerous errors in multithreaded programming, and despite intensive studies, it remains a notorious
cause of failures in concurrent systems. Detecting data races is already a hard problem, and yet it is even harder for a programmer
to decide whether or how a reported data race can appear in the actual program execution. In this paper we propose an algorithm for generating debugging
aid information called witnesses, which are concrete thread schedules that can deterministically trigger the data races. More specifically, given a concrete
execution trace, e.g. non-erroneous one which may have triggered a warning in Eraser-style data race detectors, we use a symbolic
analysis based on SMT solvers to search for a data race witness among alternative interleavings of events of that trace. Our
symbolic analysis precisely encodes the sequential consistency semantics using a scalable predictive model to ensure that
the reported witness is always feasible.

KeywordsData Race–Debug–SMT–Concurrent Programs

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