Prepare for 0.21.0 release (#1402)

This follows the applicable pre-release steps from
https://github.com/immunant/c2rust/wiki/Release-Process. Much of those
don't apply due to our outdated nightly. I also fixed the backwards
compatible `cargo +stable clippy` warnings, too.

Author: kkysen

Cargo.lock

@@ -24,7 +24,7 @@ exclude = [
 ]
 
 [workspace.package]
-version = "0.20.0"
+version = "0.21.0"
 authors = ["The C2Rust Project Developers <[email protected]>"]
 edition = "2021"
 rust-version = "1.65"

Cargo.toml

@@ -44,7 +44,7 @@ The manual is still a work-in-progress, so if you can't find something please le
 ### Prerequisites
 
 C2Rust requires LLVM 7 or later with its corresponding clang compiler and libraries.
-Python 3.6 or later, CMake 3.4.3 or later, and openssl (1.0) are also required. These prerequisites may be installed with the following commands, depending on your platform:
+Python 3.6 or later, CMake 3.5 or later, and openssl (1.0) are also required. These prerequisites may be installed with the following commands, depending on your platform:
 
 - **Ubuntu 18.04, Debian 10, and later:**
 

README.md

@@ -5,7 +5,7 @@ edition = "2021"
 
 [dependencies]
 libc = "0.2"
-c2rust-analysis-rt = { path = "../../runtime", optional = true, version = "0.20.0" }
+c2rust-analysis-rt = { path = "../../runtime", optional = true, version = "0.21.0" }
 
 [features]
 miri = []

analysis/tests/lighttpd-minimal/Cargo.toml

@@ -5,7 +5,7 @@ edition = "2021"
 
 [dependencies]
 libc = "0.2"
-c2rust-analysis-rt = { path = "../../runtime", optional = true, version = "0.20.0" }
+c2rust-analysis-rt = { path = "../../runtime", optional = true, version = "0.21.0" }
 
 [features]
 miri = []

analysis/tests/lighttpd/Cargo.toml

@@ -6,7 +6,7 @@ edition = "2021"
 
 [dependencies]
 libc = "0.2"
-c2rust-analysis-rt = { path = "../../runtime", optional = true, version = "0.20.0" }
+c2rust-analysis-rt = { path = "../../runtime", optional = true, version = "0.21.0" }
 
 [features]
 miri = []

analysis/tests/minimal/Cargo.toml

@@ -7,7 +7,7 @@ edition = "2021"
 
 [dependencies]
 libc = "0.2"
-c2rust-analysis-rt = { path = "../../runtime", optional = true, version = "0.20.0" }
+c2rust-analysis-rt = { path = "../../runtime", optional = true, version = "0.21.0" }
 
 [features]
 miri = []

analysis/tests/misc/Cargo.toml

@@ -16,7 +16,7 @@ publish = false
 polonius-engine = "0.13.0"
 rustc-hash = "1.1.0"
 bitflags = "1.3.2"
-c2rust-pdg = { path = "../pdg", version = "0.20.0"}
+c2rust-pdg = { path = "../pdg", version = "0.21.0"}
 bincode = "1.0"
 serde = "1.0"
 assert_matches = "1.5.0"
@@ -33,11 +33,11 @@ toml_edit = "0.19.8"
 sha2 = "0.10.8"
 
 [build-dependencies]
-c2rust-build-paths = { path = "../c2rust-build-paths", version = "0.20.0" }
+c2rust-build-paths = { path = "../c2rust-build-paths", version = "0.21.0" }
 print_bytes = "1.1"
 
 [dev-dependencies]
-c2rust-build-paths = { path = "../c2rust-build-paths", version = "0.20.0" }
+c2rust-build-paths = { path = "../c2rust-build-paths", version = "0.21.0" }
 clap = { version = "4.1.9", features = ["derive"] }
 shlex = "1.3.0"
 

c2rust-analyze/Cargo.toml

@@ -1179,6 +1179,7 @@ fn run(tcx: TyCtxt) {
     }
 }
 
+#[allow(clippy::too_many_arguments)]
 fn run2<'tcx>(
     pointwise_fn_ldid: Option<LocalDefId>,
     tcx: TyCtxt<'tcx>,

c2rust-analyze/src/analyze.rs

@@ -244,19 +244,16 @@ fn run_polonius<'tcx>(
     for constraint in tcx.predicates_of(mir.source.def_id()).predicates {
         // FIXME: there should be a subset relation generated for function arguments
         // such as `arg: &'a &'b &'c`, i.e. 'c: 'b, 'b: 'a, and 'c: 'a
-        match &constraint.0.kind().skip_binder() {
-            PredicateKind::RegionOutlives(OutlivesPredicate(a, b)) => match (a.kind(), b.kind()) {
-                (ReEarlyBound(eba), ReEarlyBound(ebb)) => {
-                    match (origin_map.get(&eba.def_id), origin_map.get(&ebb.def_id)) {
-                        (Some(origin_a), Some(origin_b)) => {
-                            facts.known_placeholder_subset.push((*origin_a, *origin_b));
-                        }
-                        _ => (),
-                    }
+        if let PredicateKind::RegionOutlives(OutlivesPredicate(a, b)) =
+            &constraint.0.kind().skip_binder()
+        {
+            if let (ReEarlyBound(eba), ReEarlyBound(ebb)) = (a.kind(), b.kind()) {
+                if let (Some(origin_a), Some(origin_b)) =
+                    (origin_map.get(&eba.def_id), origin_map.get(&ebb.def_id))
+                {
+                    facts.known_placeholder_subset.push((*origin_a, *origin_b));
                 }
-                _ => (),
-            },
-            _ => (),
+            }
         }
     }