Fast Constraint Synthesis for C++ Function Templates

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" summary

A Clang frontend implements a lightweight interprocedural static analysis that encodes uses in a function body as constraints, composes them with conjunctions and disjunctions to model overloading, and applies a linear-time minimizer to keep synthesis fast. The tool processes 110k lines in <1.5s, synthesizes nontrivial constraints for 30–40% of function templates in STL algorithms and Boost special functions, and shortens compiler error output by about 56.6% and 63.8% respectively.

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" chapters (9)

1. 0:00Constraint synthesis for C++ templates
2. 1:50Manual constraints in C++20 limits
3. 3:17Three-step constraint synthesis
4. 5:44Minimizing constraints fast
5. 6:25Implementation on standard libraries
6. 7:48Compiler error message length
7. 9:16Speed versus precision trade-offs
8. 10:17Conclusion and future work
9. 11:02Q&A

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