Boost the Impact of Continuous Formal Verification in Industry

Software model checking has experienced significant progress in the last two decades, however, one of its major bottlenecks for practical applications remains its scalability and adaptability. Here, we describe an approach to integrate software model checking techniques into the DevOps culture by exploiting practices such as continuous integration and regression tests. In particular, our proposed approach looks at the modifications to the software system since its last verification, and submits them to a continuous formal verification process, guided by a set of regression test cases. Our vision is to focus on the developer in order to integrate formal verification techniques into the developer workflow by using their main software development methodologies and tools.Comment: 7 page

SMT-Based Refutation of Spurious Bug Reports in the Clang Static Analyzer

We describe and evaluate a bug refutation extension for the Clang Static Analyzer (CSA) that addresses the limitations of the existing built-in constraint solver. In particular, we complement CSA's existing heuristics that remove spurious bug reports. We encode the path constraints produced by CSA as Satisfiability Modulo Theories (SMT) problems, use SMT solvers to precisely check them for satisfiability, and remove bug reports whose associated path constraints are unsatisfiable. Our refutation extension refutes spurious bug reports in 8 out of 12 widely used open-source applications; on average, it refutes ca. 7% of all bug reports, and never refutes any true bug report. It incurs only negligible performance overheads, and on average adds 1.2% to the runtime of the full Clang/LLVM toolchain. A demonstration is available at {\tt https://www.youtube.com/watch?v=ylW5iRYNsGA}.Comment: 4 page

Cultivar de Arroz de Terras Altas BRSGO Serra Dourada: Desempenho Produtivo em Roraima.

bitstream/item/135279/1/COT-175-N77.pd

Evolução do Cultivo e Custo de Produção do Arroz Irrigado em Roraima

bitstream/item/35102/1/COT-47-2010-ID-13-1.pd

Arroz Vermelho: Orientações técnicas para o manejo em lavouras de arroz irrigado em várzeas de Roraima.

bitstream/item/37030/1/DOC-41-2010-ID-44-1.pd

Desempenho produtivo da cultivar de Arroz de terras altas BRS Sertaneja em Roraima no período de 2002 a 2006.

bitstream/item/41044/1/BPD-25-2010-ID-54.pd

BRS Tropical: Nova cultivar de Arroz Para as Várzeas de Roraima.

bitstream/item/24082/1/tropical.pd