ci: semver-checks should run on rust stable

.github/workflows/semver-checks.yml

@@ -5,7 +5,7 @@ name: Check semver breaks
 
 jobs:
   API:
-    name: API - nightly toolchain
+    name: API - stable toolchain
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
@@ -15,10 +15,7 @@ jobs:
         with:
           fetch-depth: 0 # we need full history for cargo semver-checks
       - name: "Install Rustup"
-        uses: dtolnay/rust-toolchain@nightly
-      - name: "Select nightly-version"
-        run: |
-          rustup default $(cat nightly-version)
+        uses: dtolnay/rust-toolchain@stable
       - name: "Install cargo-binstall"
         uses: cargo-bins/cargo-binstall@main
       - name: "Binstall cargo-semver-checks"

contrib/check-semver.sh

@@ -12,9 +12,6 @@
 
 set -euo pipefail
 
-# Our nightly version.
-NIGHTLY=$(cat nightly-version)
-
 # These are the hardcoded flags that cargo semver-checks uses
 # under the hood to invoke rustdoc.
 RUSTDOCFLAGS="-Z unstable-options --document-private-items --document-hidden-items --output-format=json --cap-lints=allow"
@@ -29,9 +26,6 @@ else
 fi
 
 main() {
-    # we need cargo nightly to generate the JSON files from cargo doc.
-    need_nightly
-
     # On current commit:
     # 1. bitcoin: all-features and no-default-features.
     generate_json_files_all_features "bitcoin" "current"
@@ -108,7 +102,7 @@ main() {
 # Run cargo doc with the cargo semver-checks rustdoc flags.
 # We don't care about dependencies.
 run_cargo_doc() {
-    RUSTDOCFLAGS="$RUSTDOCFLAGS" cargo +"$NIGHTLY" doc --no-deps "$@"
+    RUSTDOCFLAGS="$RUSTDOCFLAGS" RUSTC_BOOTSTRAP=1 cargo doc --no-deps "$@"
 }
 
 # Run cargo semver-check
@@ -122,7 +116,7 @@ run_cargo_semver_check() {
     # semver check fails.
     # We check that manually later.
     set +e
-    cargo +"$NIGHTLY" semver-checks -v --baseline-rustdoc "$crate-master-$variant.json" --current-rustdoc "$crate-current-$variant.json" > "$crate-$variant-semver.txt" 2>&1
+    cargo semver-checks -v --baseline-rustdoc "$crate-master-$variant.json" --current-rustdoc "$crate-current-$variant.json" > "$crate-$variant-semver.txt" 2>&1
     set -e
 }
 
@@ -191,19 +185,6 @@ check_for_breaking_changes() {
     fi
 }
 
-# Safekeeping: check if we have a nightly compiler.
-need_nightly() {
-    cargo_ver=$(cargo +"$NIGHTLY" --version)
-    if echo "$cargo_ver" | grep -q -v nightly; then
-        err "Need a nightly compiler; have $cargo_ver"
-    fi
-}
-
-err() {
-    echo "$1" >&2
-    exit 1
-}
-
 #
 # Main script
 #