2026-07-28T20:03:53Z https://drops.dagstuhl.de/oai

oai:drops-oai.dagstuhl.de:26718 2026-07-28T09:32:41Z ddc:004 open_access

Out of the Loop No More: Online Abstract Debugging with Loop Stepping (Short Paper) Alvim, João Steevens, Maarten Scholliers, Christophe Debugging Abstract Interpretation Traditional debugging makes it practically impossible to manually explore all execution paths, often leaving hypotheses insufficiently explored. Abstract debugging addresses this problem by safely over-approximating all program behaviours through a familiar stepping interface. However, existing approaches operate offline, pre-computing fixed loop summaries that developers cannot interactively refine or inspect at the individual iteration level. In this paper, we propose online abstract debugging, which performs abstract interpretation on demand as the developer steps through the program. This novel architecture enables loop stepping: developers can step into a loop body for precise, iteration-specific states, or step-over to obtain a coarser summary. By interleaving analysis with execution, developers gain direct control over the cost-precision trade-off, computing high precision only where needed to settle a hypothesis. We instantiate this model for WebAssembly and present a prototype implementation, demonstrating that developers can effectively draw sound conclusions about complex, potentially non-terminating looping programs. Schloss Dagstuhl – Leibniz-Zentrum für Informatik João Alvim and Maarten Steevens and Christophe Scholliers 2026 Is Part Of OASIcs, Volume 144, 15th Symposium on Languages, Applications and Technologies (SLATE 2026) InProceedings Text doc-type:ResearchArticle publishedVersion application/pdf doi:10.4230/OASIcs.SLATE.2026.20 urn:nbn:de:0030-drops-267180 https://drops.dagstuhl.de/entities/document/10.4230/OASIcs.SLATE.2026.20 eng https://creativecommons.org/licenses/by/4.0/legalcode