diff --git a/community-build/community-projects/PPrint b/community-build/community-projects/PPrint
index 7a668f52cc19..231bc187faad 160000
--- a/community-build/community-projects/PPrint
+++ b/community-build/community-projects/PPrint
@@ -1 +1 @@
-Subproject commit 7a668f52cc19addd4f24e41ef11714a8e2b0e405
+Subproject commit 231bc187faad172b55af4ddc50c30228a56b2ebd
diff --git a/community-build/community-projects/fansi b/community-build/community-projects/fansi
index c30b5cd3cb6c..21d1db61a315 160000
--- a/community-build/community-projects/fansi
+++ b/community-build/community-projects/fansi
@@ -1 +1 @@
-Subproject commit c30b5cd3cb6ca94cc9f489b75b4920e8d0b71914
+Subproject commit 21d1db61a315b31636dfd6515f346454b21ac5f6
diff --git a/community-build/community-projects/geny b/community-build/community-projects/geny
index f1804705fecf..03ff552cd384 160000
--- a/community-build/community-projects/geny
+++ b/community-build/community-projects/geny
@@ -1 +1 @@
-Subproject commit f1804705fecfd41bf4f9a2cde24b7549fd3315a5
+Subproject commit 03ff552cd3846939e1686481b3623ea6d06d1d24
diff --git a/community-build/community-projects/os-lib b/community-build/community-projects/os-lib
index 36af8391f783..1a848dc584dd 160000
--- a/community-build/community-projects/os-lib
+++ b/community-build/community-projects/os-lib
@@ -1 +1 @@
-Subproject commit 36af8391f7836a69f6c4d0de7b41608e5b82a898
+Subproject commit 1a848dc584ddfdcf48b7075a4292e09d0b8c00e0
diff --git a/community-build/community-projects/requests-scala b/community-build/community-projects/requests-scala
index 70e8c48a3d74..139dbe6418f1 160000
--- a/community-build/community-projects/requests-scala
+++ b/community-build/community-projects/requests-scala
@@ -1 +1 @@
-Subproject commit 70e8c48a3d74320758c0f2f876ff1e69b8061b81
+Subproject commit 139dbe6418f1ecee09b020086fc2fc9e844e57e3
diff --git a/community-build/community-projects/scas b/community-build/community-projects/scas
index 1cdf2980e26a..91b1de233de7 160000
--- a/community-build/community-projects/scas
+++ b/community-build/community-projects/scas
@@ -1 +1 @@
-Subproject commit 1cdf2980e26a38e481ab4fd15fdc104febcfcccf
+Subproject commit 91b1de233de7128e57aca1303e099b1a5499807f
diff --git a/community-build/community-projects/sourcecode b/community-build/community-projects/sourcecode
index 0143c7719a90..4ae2049a4d62 160000
--- a/community-build/community-projects/sourcecode
+++ b/community-build/community-projects/sourcecode
@@ -1 +1 @@
-Subproject commit 0143c7719a9058e3e26f4826071ea63eef109cb6
+Subproject commit 4ae2049a4d628cf85b9bf556333c9f6edb9deee5
diff --git a/community-build/community-projects/upickle b/community-build/community-projects/upickle
index b22789b8b14d..b5fe468f8665 160000
--- a/community-build/community-projects/upickle
+++ b/community-build/community-projects/upickle
@@ -1 +1 @@
-Subproject commit b22789b8b14d21f54b2e79807dd415373bf08480
+Subproject commit b5fe468f8665b12d09a733e7a1b419cf26ad2f88
diff --git a/community-build/community-projects/utest b/community-build/community-projects/utest
index d5d1482f25e9..654376f41f83 160000
--- a/community-build/community-projects/utest
+++ b/community-build/community-projects/utest
@@ -1 +1 @@
-Subproject commit d5d1482f25e96d315e1ba0d9404f9e0ca6bc95c1
+Subproject commit 654376f41f8380a44fdb70f693016f25633ae1be
diff --git a/sbt-bridge/src/xsbt/CompilerClassLoader.java b/sbt-bridge/src/xsbt/CompilerClassLoader.java
index 1ce573148e47..bd1abce4adb5 100644
--- a/sbt-bridge/src/xsbt/CompilerClassLoader.java
+++ b/sbt-bridge/src/xsbt/CompilerClassLoader.java
@@ -119,4 +119,4 @@ private static ClassLoader computeFixedLoader(ClassLoader bridgeLoader) {
       throw new RuntimeException(e);
     }
   }
-}
+}
\ No newline at end of file
diff --git a/sbt-bridge/src/xsbt/CompilerInterface.java b/sbt-bridge/src/xsbt/CompilerInterface.java
index 1af338fe93de..9f09ebbdeb06 100644
--- a/sbt-bridge/src/xsbt/CompilerInterface.java
+++ b/sbt-bridge/src/xsbt/CompilerInterface.java
@@ -6,36 +6,50 @@
 import xsbti.AnalysisCallback;
 import xsbti.Logger;
 import xsbti.Reporter;
-import xsbti.Severity;
 import xsbti.compile.*;
 
-import java.io.File;
-
-import dotty.tools.dotc.core.Contexts.ContextBase;
 import dotty.tools.dotc.Main;
-import dotty.tools.dotc.interfaces.*;
 
 import java.lang.reflect.InvocationTargetException;
-import java.net.URLClassLoader;
+import java.io.File;
 
 /**
  * The new compiler interface is [[dotty.tools.xsbt.CompilerBridge]] that extends the new `xsbti.CompilerInterface2`.
  * This interface is kept for compatibility with Mill and the sbt 1.3.x series.
  */
 public final class CompilerInterface {
-  public CachedCompiler newCompiler(String[] options, Output output, Logger initialLog, Reporter initialDelegate) {
-    // The classloader that sbt uses to load the compiler bridge is broken
-    // (see CompilerClassLoader#fixBridgeLoader for details). To workaround
-    // this we construct our own ClassLoader and then run the following code
-    // with it:
-    //   new CachedCompilerImpl(options, output)
+  public CachedCompiler newCompiler(String[] options, Output output, Logger initialLog, Reporter initialDelegate) throws java.lang.Exception {
+    if(isClassLoaderValid()) {
+      return new CachedCompilerImpl(options, output);
+    } else {
+      initialLog.warn(() ->
+        "The compiler class loader is badly configured.\n" +
+        "Consider using a more recent version of your build tool:\n" +
+        " - sbt >= 1.4.0 and sbt-dotty >= 1.5.0\n" +
+        " - Mill >= 0.9.3-21-002361\n" +
+        " - Bloop >= 1.4.6-23-20a501bc"
+      );
+      // To workaround the wrong class loader, we construct our own and run
+      // the following code with it:
+      //   new CachedCompilerImpl(options, output)
+      try {
+        ClassLoader bridgeLoader = this.getClass().getClassLoader();
+        ClassLoader fixedLoader = CompilerClassLoader.fixBridgeLoader(bridgeLoader);
+        Class<?> cciClass = fixedLoader.loadClass("xsbt.CachedCompilerImpl");
+        return (CachedCompiler) cciClass.getConstructors()[0].newInstance(options, output);
+      } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | InvocationTargetException e) {
+        throw new RuntimeException(e);
+      }
+    }
+  }
 
+  private boolean isClassLoaderValid() {
+    // Check that the `xsbti.*` classes are loaded from the same class loader in the compiler and the bridge
+    ClassLoader compilerClassLoader = Main.class.getClassLoader();
+    Class<Logger> clazz = Logger.class;
     try {
-      ClassLoader bridgeLoader = this.getClass().getClassLoader();
-      ClassLoader fixedLoader = CompilerClassLoader.fixBridgeLoader(bridgeLoader);
-      Class<?> cciClass = fixedLoader.loadClass("xsbt.CachedCompilerImpl");
-      return (CachedCompiler) cciClass.getConstructors()[0].newInstance(options, output);
-    } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | InvocationTargetException e) {
+      return compilerClassLoader.loadClass("xsbti.Logger") == clazz;
+    } catch (ClassNotFoundException e) {
       throw new RuntimeException(e);
     }
   }