DataDog · AlexeyKuznetsov-DD · May 30, 2026 · May 30, 2026 · May 30, 2026 · May 30, 2026
@@ -249,6 +249,8 @@ default:
     # GitLab's cache helper restores .gradle as root, but we run as non-root-user (uid 1001),
     # and Gradle does `chmod 700 .gradle` on startup which requires user ownership.
     - sudo chown -R 1001:1001 .gradle
+    # Detect and fix corrupted Gradle cache: "FATAL: unexpected EOF"
+    - .gitlab/gradle-cache/mitigate_corrupted_gradle_cache.sh "$GRADLE_VERSION"
   after_script:
     - *cgroup_info
     - *container_info

@@ -0,0 +1,136 @@
+import java.io.File;
+import java.io.IOException;
+import java.lang.reflect.Method;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.Comparator;
+import java.util.List;
+import java.util.Map;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+
+/**
+ * Band-aid for "FATAL: unexpected EOF" during GitLab cache extraction.
+ * <p>
+ * This removes only the damaged workspaces so Gradle regenerates them.
+ */
+class CorruptedGradleCacheMitigator {
+  private static final Path CACHES_DIR = Path.of(".gradle/caches");
+
+  // Immutable-workspace categories and the directory depth at which their workspaces live.
+  private static final Map<String, Integer> WORKSPACE_CATEGORIES =
+      Map.of("dependencies-accessors", 1, "groovy-dsl", 1, "kotlin-dsl", 2, "transforms", 1);
+
+  // Gradle temporary workspaces are <workspace>-<uuid> and may legitimately lack metadata.bin.
+  private static final Pattern TEMPORARY_WORKSPACE =
+      Pattern.compile(
+          ".*-[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}");
+
+  // Gradle's own metadata reader, resolved reflectively.
+  private static Object metadataStore;
+  private static Method metadataLoadMethod;
+
+  public static void main(String[] args) throws IOException {
+    var gradleVersion = args[0];
+
+    var damaged = new ArrayList<Path>();
+    try {
+      loadMetadataReader();
+    } catch (Throwable e) {
+      System.out.println("Gradle metadata reader unavailable; leaving cache unchanged");
+      e.printStackTrace();
+      return;
+    }
+
+    try {
+      for (var workspace : enumerateWorkspaces(gradleVersion)) {
+        if (isDamaged(workspace)) {
+          damaged.add(workspace);
+        }
+      }
+    } catch (Throwable e) {
+      System.out.println("Failed to collect damaged workspaces");
+      e.printStackTrace();
+      return;
+    }
+
+    if (!damaged.isEmpty()) {
+      System.out.println("Damaged Gradle metadata found, removing:");
+
+      for (var workspace : damaged) {
+        System.out.println("  - " + workspace);
+        try {
+          remove(workspace);
+        } catch (Throwable e) {
+          e.printStackTrace();
+        }
+      }
+    }
+  }
+
+  private static List<Path> enumerateWorkspaces(String gradleVersion) throws IOException {
+    var versionDir = CACHES_DIR.resolve(gradleVersion);
+    var workspaces = new ArrayList<Path>();
+    for (var category : WORKSPACE_CATEGORIES.entrySet()) {
+      collectAtDepth(versionDir.resolve(category.getKey()), category.getValue(), workspaces);
+    }
+    return workspaces;
+  }
+
+  private static void collectAtDepth(Path dir, int depth, List<Path> out) throws IOException {
+    if (!Files.isDirectory(dir)) {
+      return;
+    }
+
+    if (depth == 0) {
+      out.add(dir);
+      return;
+    }
+
+    try (var entries = Files.list(dir)) {
+      for (var child : entries.filter(Files::isDirectory).collect(Collectors.toList())) {
+        collectAtDepth(child, depth - 1, out);
+      }
+    }
+  }
+
+  private static void loadMetadataReader() {
+    try {
+      var storeClass = Class.forName(
+          "org.gradle.internal.execution.history.impl.DefaultImmutableWorkspaceMetadataStore");
+      metadataStore = storeClass.getDeclaredConstructor().newInstance();
+      metadataLoadMethod = storeClass.getMethod("loadWorkspaceMetadata", File.class);
+    } catch (Throwable e) {
+      throw new IllegalStateException("Failed to load Gradle metadata reader", e);
+    }
+  }
+
+  private static boolean isDamaged(Path workspace) {
+    if (TEMPORARY_WORKSPACE.matcher(workspace.getFileName().toString()).matches()) {
+      return false;
+    }
+
+    if (!Files.isRegularFile(workspace.resolve("metadata.bin"))) {
+      return true;
+    }
+
+    // A successful return means Gradle's own reader fully deserialized `metadata.bin`.
+    try {
+      metadataLoadMethod.invoke(metadataStore, workspace.toFile());
+      return false;
+    } catch (Throwable e) {
+      return true; // truncated/unreadable -> remove it
+    }
+  }
+
+  private static void remove(Path workspace) {
+    try (var paths = Files.walk(workspace)) {
+      for (var path : paths.sorted(Comparator.reverseOrder()).collect(Collectors.toList())) {
+        Files.deleteIfExists(path);
+      }
+    } catch (Throwable e) {
+      throw new IllegalStateException("Failed to remove: " + workspace, e);
+    }
+  }
+}
@@ -0,0 +1,37 @@
+#!/usr/bin/env bash
+
+set -uo pipefail
+
+gradle_version="${1:?usage: mitigate_corrupted_gradle_cache.sh <gradle-version>}"
+script_dir="$(cd "$(dirname "$0")" && pwd)"
+
+java_home="${JAVA_25_HOME:-}"
+java_bin="${java_home:+$java_home/bin/}java"
+javac_bin="${java_home:+$java_home/bin/}javac"
+
+gradle_lib=""
+for gradle_home in "${GRADLE_USER_HOME:-$PWD/.gradle}" "$HOME/.gradle"; do
+  [[ -d "$gradle_home/wrapper/dists" ]] || continue
+  gradle_lib="$(
+    find "$gradle_home/wrapper/dists" -path "*/gradle-${gradle_version}/lib" -type d -print -quit \
+      2>/dev/null
+  )"
+  [[ -n "$gradle_lib" ]] && break
+done
+if [[ -z "$gradle_lib" ]]; then
+  echo "Gradle $gradle_version distribution not found; leaving cache unchanged." >&2
+  exit 0
+fi
+
+build_dir="$(mktemp -d)"
+trap 'rm -rf "$build_dir"' EXIT
+
+# -proc:none keeps the compiler from running annotation processors bundled in the Gradle jars.
+if ! "$javac_bin" -proc:none -classpath "$gradle_lib/*" -d "$build_dir" \
+    "$script_dir/CorruptedGradleCacheMitigator.java"; then
+  echo "Could not compile CorruptedGradleCacheMitigator; leaving cache unchanged." >&2
+  exit 0
+fi
+
+"$java_bin" -classpath "$build_dir:$gradle_lib/*" \
+  CorruptedGradleCacheMitigator "$gradle_version"