Investigate and fix FreeBSD 14.3 CI failure (#372)

.cirrus.yml

@@ -2,13 +2,15 @@ task:
   freebsd_instance:
     cpu: 1
     matrix:
-      - image_family: freebsd-15-0-amd64-zfs
-      - image_family: freebsd-14-3
+      - image_name: freebsd-15-1-release-amd64-ufs
+      - image_name: freebsd-14-5-release-amd64-ufs
   install_script: pkg install -y bash git autoconf automake libtool groff pkgconf
   kernel_src_script: |
     uname -r
-    if [[ $(uname -r) == "14.3-RELEASE" ]]; then
-      git clone --branch releng/14.3 https://git.FreeBSD.org/src.git /usr/src
+    if [ ! -f /usr/src/sys/kern/kern_lockf.c ]; then
+      rm -rf /usr/src
+      rel=$(uname -r | sed 's/-p[0-9]*$//; s/-RELEASE$//')
+      git clone --branch "releng/${rel}" https://git.FreeBSD.org/src.git /usr/src
     fi;
   build_script:
     - ./Configure -n freebsd

.github/workflows/build.yml

@@ -62,7 +62,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        release: ["15.1", "14.3"]
+        release: ["15.1", "14.5"]
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v7
@@ -85,7 +85,15 @@ jobs:
           # unless the sources are there.  Unpack just usr/src/sys out of the
           # release source set; that is ~15s and about 580MB on disk.
           rel=$(uname -r | sed 's/-p[0-9]*$//')
-          fetch -o /tmp/src.txz "https://download.freebsd.org/releases/$(uname -m)/${rel}/src.txz"
+          if ! fetch -o /tmp/src.txz "https://download.freebsd.org/releases/$(uname -m)/${rel}/src.txz"; then
+            # FreeBSD removes release artifacts from download.freebsd.org
+            # once a release reaches EOL, but the old-releases archive keeps
+            # them.  Fall back there so a release removed from the main
+            # mirror can still provide its sources.
+            echo "warning: source set not on download.freebsd.org, trying archive.freebsd.org"
+            rm -f /tmp/src.txz
+            fetch -o /tmp/src.txz "https://archive.freebsd.org/old-releases/$(uname -m)/${rel}/src.txz"
+          fi
           tar -xf /tmp/src.txz -C / usr/src/sys
 
           # autotools build, out of tree so the source tree stays pristine for