# Toward Type-Preserving Compilation of Coq, at POPL17 SRC

Almost two months ago, my colleagues in the Northeastern PRL wrote about three of our POPL 2017 Student Research Competition submissions. There was fourth submission, but because I was hard at work completing proofs, it wasn’t announced.

## Toward Type-Preserving Compilation of Coq

Toward Type-Preserving Compilation of Coq

William J. Bowman

2016

A type-preserving compiler guarantees that a well-typed source program is compiled to a well-typed target program. Type-preserving compilation can support correctness guarantees about compilers, and optimizations in compiler intermediate languages (ILs). For instance, Morrisett

et al.(1998) use type-preserving compilation from System F to a Typed Assembly Languages (TAL) to guarantee absence of stuckness, even when linking with arbitrary (well-typed) TAL code. Tarditiet al.(1996) develop a compiler for ML that uses a typed IL for optimizations.We develop type-preserving closure conversion for the Calculus of Constructions (CC). Typed closure conversion has been studied for simply-typed languages (Minamide1996, Ahmed2008, New2016) and polymorphic languages (Minamide1996, Morrisett1998). Dependent types introduce new challenges to both typed closure conversion in particular and to type preservation proofs in general.