diff --git a/gcc/rust/checks/errors/borrowck/ffi-polonius/Cargo.lock b/gcc/rust/checks/errors/borrowck/ffi-polonius/Cargo.lock
index 73368397082c..71a1b585206b 100644
--- a/gcc/rust/checks/errors/borrowck/ffi-polonius/Cargo.lock
+++ b/gcc/rust/checks/errors/borrowck/ffi-polonius/Cargo.lock
@@ -2,6 +2,26 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "aho-corasick"
+version = "0.7.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b4f55bd91a0978cbfd91c457a164bab8b4001c833b7f323132c0a4e1922dd44e"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "atty"
+version = "0.2.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d9b39be18770d11421cdb1b9947a45dd3f37e93092cbf377614828a319d5fee8"
+dependencies = [
+ "hermit-abi",
+ "libc",
+ "winapi",
+]
+
 [[package]]
 name = "cfg-if"
 version = "1.0.0"
@@ -14,13 +34,49 @@ version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a0afaad2b26fa326569eb264b1363e8ae3357618c43982b3f285f0774ce76b69"
 
+[[package]]
+name = "env_logger"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c90bf5f19754d10198ccb95b70664fc925bd1fc090a0fd9a6ebc54acc8cd6272"
+dependencies = [
+ "atty",
+ "humantime",
+ "log",
+ "regex",
+ "termcolor",
+]
+
 [[package]]
 name = "ffi-polonius"
 version = "0.1.0"
 dependencies = [
+ "env_logger",
+ "log",
  "polonius-engine",
 ]
 
+[[package]]
+name = "hermit-abi"
+version = "0.1.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "62b467343b94ba476dcb2500d242dadbb39557df889310ac77c5d99100aaac33"
+dependencies = [
+ "libc",
+]
+
+[[package]]
+name = "humantime"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9a3a5bfb195931eeb336b2a7b4d761daec841b97f947d34394601737a7bba5e4"
+
+[[package]]
+name = "libc"
+version = "0.2.133"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c0f80d65747a3e43d1596c7c5492d95d5edddaabd45a7fcdb02b95f644164966"
+
 [[package]]
 name = "log"
 version = "0.4.14"
@@ -30,6 +86,12 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "memchr"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
+
 [[package]]
 name = "polonius-engine"
 version = "0.13.0"
@@ -41,8 +103,65 @@ dependencies = [
  "rustc-hash",
 ]
 
+[[package]]
+name = "regex"
+version = "1.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4c4eb3267174b8c6c2f654116623910a0fef09c4753f8dd83db29c48a0df988b"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.6.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a3f87b73ce11b1619a3c6332f45341e0047173771e8b8b73f87bfeefb7b56244"
+
 [[package]]
 name = "rustc-hash"
 version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "08d43f7aa6b08d49f382cde6a7982047c3426db949b1424bc4b7ec9ae12c6ce2"
+
+[[package]]
+name = "termcolor"
+version = "1.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bab24d30b911b2376f3a13cc2cd443142f0c81dda04c118693e35b3835757755"
+dependencies = [
+ "winapi-util",
+]
+
+[[package]]
+name = "winapi"
+version = "0.3.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"
+dependencies = [
+ "winapi-i686-pc-windows-gnu",
+ "winapi-x86_64-pc-windows-gnu",
+]
+
+[[package]]
+name = "winapi-i686-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
+
+[[package]]
+name = "winapi-util"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "70ec6ce85bb158151cae5e5c87f95a8e97d2c0c4b001223f33a334e3ce5de178"
+dependencies = [
+ "winapi",
+]
+
+[[package]]
+name = "winapi-x86_64-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
diff --git a/gcc/rust/checks/errors/borrowck/ffi-polonius/Cargo.toml b/gcc/rust/checks/errors/borrowck/ffi-polonius/Cargo.toml
index 809635620e79..e17f1e3ca0e2 100644
--- a/gcc/rust/checks/errors/borrowck/ffi-polonius/Cargo.toml
+++ b/gcc/rust/checks/errors/borrowck/ffi-polonius/Cargo.toml
@@ -8,3 +8,5 @@ crate-type = ["staticlib"]
 
 [dependencies]
 polonius-engine = "0.13"
+log = "0.4"
+env_logger = "0.9"
diff --git a/gcc/rust/checks/errors/borrowck/ffi-polonius/src/lib.rs b/gcc/rust/checks/errors/borrowck/ffi-polonius/src/lib.rs
index ca654e17a770..da3cc7a39d52 100644
--- a/gcc/rust/checks/errors/borrowck/ffi-polonius/src/lib.rs
+++ b/gcc/rust/checks/errors/borrowck/ffi-polonius/src/lib.rs
@@ -1,6 +1,7 @@
 //! There are two main components to the polonius-engine library: Facts and
 //! Output.
 
+use log::{debug, info};
 use polonius_engine::{AllFacts, Atom, FactTypes, Output};
 
 use std::convert::From;
@@ -8,6 +9,7 @@ use std::convert::From;
 #[derive(Debug, Clone, Copy, Default)]
 struct GccrsPolonius;
 
+/// This represents an `HirId` as emitted by `gccrs`.
 #[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
 struct GccrsAtom(usize);
 
@@ -30,6 +32,7 @@ impl From<GccrsAtom> for usize {
 }
 
 impl FactTypes for GccrsPolonius {
+    // FIXME: Do we want anything else than the `HirId` here?
     type Origin = GccrsAtom;
     type Loan = GccrsAtom;
     type Point = GccrsAtom;
@@ -46,8 +49,12 @@ pub struct FfiGccrsPolonius(pub(crate) AllFacts<GccrsPolonius>);
 /// and return.
 #[no_mangle]
 pub unsafe extern "C" fn polonius_init() -> *mut FfiGccrsPolonius {
+    env_logger::init();
+
+    info!("initializing handle");
+
     let facts = AllFacts::default();
-    eprintln!("[polonius] init");
+
     Box::into_raw(Box::new(FfiGccrsPolonius(facts)))
 }
 
@@ -57,8 +64,9 @@ pub unsafe extern "C" fn polonius_init() -> *mut FfiGccrsPolonius {
 /// performed.
 #[no_mangle]
 pub unsafe extern "C" fn polonius_deinit(handle: *mut FfiGccrsPolonius) {
-    eprintln!("[polonius] deinit");
-    Box::from_raw(handle);
+    info!("deinitializing handle");
+
+    drop(Box::from_raw(handle));
 }
 
 /// # Safety
@@ -72,7 +80,7 @@ pub unsafe extern "C" fn polonius_var_used_at(
 ) {
     let handle = handle.as_mut().unwrap();
 
-    eprintln!("[polonius] variable {} used at {}", var_id, point_id);
+    debug!("variable {} used at {}", var_id, point_id);
 
     handle.0.var_used_at.push((var_id.into(), point_id.into()))
 }
@@ -88,10 +96,7 @@ pub unsafe extern "C" fn polonius_define_var(
 ) {
     let handle = handle.as_mut().unwrap();
 
-    eprintln!(
-        "[polonius] defining variable ([point] {}: [var] {})",
-        point_id, var_id
-    );
+    debug!("defining variable ([point] {}: [var] {})", point_id, var_id);
 
     handle
         .0
@@ -106,7 +111,7 @@ pub unsafe extern "C" fn polonius_define_var(
 pub unsafe extern "C" fn polonius_borrow_var(handle: *mut FfiGccrsPolonius) {
     let _handle = handle.as_mut().unwrap();
 
-    eprintln!("[polonius] borrowing variable");
+    debug!("borrowing variable");
 }
 
 /// # Safety
@@ -116,5 +121,7 @@ pub unsafe extern "C" fn polonius_borrow_var(handle: *mut FfiGccrsPolonius) {
 pub unsafe extern "C" fn polonius_compute(handle: *mut FfiGccrsPolonius) {
     let handle = handle.as_mut().unwrap();
 
+    info!("computing facts");
+
     Output::compute(&handle.0, polonius_engine::Algorithm::Naive, true);
 }