Fengyun Liu
ABSTRACT
Objects under initialization are fragile: some of their fields are not yet initialized. Consequently, accessing those uninitialized fields directly or indirectly may result in program crashes or abnormal behaviors at runtime.
A newly created object goes through several states during its initialization, beginning with all fields being empty until all of them are filled. However, ensuring initialization safety statically, without manual annotation of initialization states in the source code, is a challenge, due to aliasing, virtual method calls and typestate polymorphism.
In this work, we introduce a novel analysis based on abstract interpreters to ensure initialization safety. Compared to the previous approaches, our analysis is simpler and easier to extend, and it does not require any user annotations. The analysis is inter-procedural, context-sensitive and flow-insensitive, yet it has good performance thanks to local reasoning and heap monotonicity.
Supplemental Material
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Digital Library
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- Fengyun Liu. 2020. Safe initialization of objects. Ph.D. Dissertation. EPFL.Google Scholar
- Fengyun Liu, Ondřej Lhoták, Aggelos Biboudis, Paolo G. Giarrusso, and Martin Odersky. 2020. A type-and-effect system for object initialization. Proc. ACM Program. Lang., 4, OOPSLA (2020), 175:1–175:28. https://doi.org/10.1145/3428243 Google ScholarDigital Library
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Index Terms
- Safe object initialization, abstractly
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