Olivier Savary Belanger will present his FPO "Verified Extraction for Coq" on Thursday, 10/17/2019 at 10:30am in CS 401. The members of his committee are: Andrew Appel (Adviser); Examiners: Zachary Kincaid, Lennart Beringer, and Andrew Appel; Readers: David Walker and John Gregory Morrisett (Cornell University) A copy of his thesis is available upon request. Please email [ mailto:ngotsis@cs.princeton | ngotsis@cs.princeton ] if you would like a copy of the thesis. Everyone is invited to attend his talk. The talk abstract follows below. Interactive theorem provers allow for the development, in the same environment, of programs and of proofs about them. The programmatic portion of the development can then be extracted to code which is then compiled into an executable. However, unless both the extraction and compilation processes are formally verified, one has no guarantees that the proofs developed still apply to the resulting executable. This thesis describes my work on CertiCoq, a verified extraction pipeline for the Coq theorem prover composing with the CompCert C verified compiler to achieve end-toend correctness guarantees. I present a proof framework to prove optimizations over the continuation-passing style (CPS) intermediate representation (IR) used in CertiCoq. This framework has been used by me and others to prove the correctness of nontrivial optimizations. I focus on a novel proof of correctness for a shrink reduction algorithm, a transformation combining in a single pass multiple optimizations which always result in smaller terms. I also present a verified code generation translating the CPS IR into Clight, a front-end language of CompCert. I show how it interfaces with a verified garbage collector and how its proof composes with the proof of correctness of CompCert. Taken together, this thesis shows how carefuly crafted intermediate languages facilitate verification e↵ort in the context of an optimizing compiler.