diff --git a/mlir/include/mlir/Analysis/CFGLoopInfo.h b/mlir/include/mlir/Analysis/CFGLoopInfo.h
--- a/mlir/include/mlir/Analysis/CFGLoopInfo.h
+++ b/mlir/include/mlir/Analysis/CFGLoopInfo.h
@@ -18,7 +18,17 @@
 #include "mlir/IR/Dominance.h"
 #include "mlir/IR/RegionGraphTraits.h"
 #include "llvm/Analysis/LoopInfo.h"
-#include "llvm/Analysis/LoopInfoImpl.h"
+
+namespace mlir {
+class CFGLoop;
+class CFGLoopInfo;
+} // namespace mlir
+
+namespace llvm {
+// Implementation in LLVM's LoopInfoImpl.h
+extern template class LoopBase<mlir::Block, mlir::CFGLoop>;
+extern template class LoopInfoBase<mlir::Block, mlir::CFGLoop>;
+} // namespace llvm
 
 namespace mlir {
 
@@ -38,6 +48,9 @@
 public:
   CFGLoopInfo(const llvm::DominatorTreeBase<mlir::Block, false> &domTree);
 };
+
+raw_ostream &operator<<(raw_ostream &os, mlir::Block &block);
+
 } // namespace mlir
 
 #endif // MLIR_ANALYSIS_LOOPINFO_H
diff --git a/mlir/include/mlir/IR/Block.h b/mlir/include/mlir/IR/Block.h
--- a/mlir/include/mlir/IR/Block.h
+++ b/mlir/include/mlir/IR/Block.h
@@ -351,6 +351,10 @@
   void printAsOperand(raw_ostream &os, bool printType = true);
   void printAsOperand(raw_ostream &os, AsmState &state);
 
+  /// NOTE: Do not call this function, it is only used to be compatible with the
+  /// LLVM loop analysis machinery.
+  bool isLegalToHoistInto() const { return false; };
+
 private:
   /// Pair of the parent object that owns this block and a bit that signifies if
   /// the operations within this block have a valid ordering.
diff --git a/mlir/lib/Analysis/CFGLoopInfo.cpp b/mlir/lib/Analysis/CFGLoopInfo.cpp
--- a/mlir/lib/Analysis/CFGLoopInfo.cpp
+++ b/mlir/lib/Analysis/CFGLoopInfo.cpp
@@ -7,6 +7,12 @@
 //===----------------------------------------------------------------------===//
 
 #include "mlir/Analysis/CFGLoopInfo.h"
+#include "llvm/Analysis/LoopInfoImpl.h"
+
+// Explicitly instantiate the LoopBase and LoopInfoBase classes defined in
+// LoopInfoImpl.h for CFGLoops
+template class llvm::LoopBase<mlir::Block, mlir::CFGLoop>;
+template class llvm::LoopInfoBase<mlir::Block, mlir::CFGLoop>;
 
 using namespace mlir;
 
@@ -17,3 +23,8 @@
     const llvm::DominatorTreeBase<mlir::Block, false> &domTree) {
   analyze(domTree);
 }
+
+raw_ostream &mlir::operator<<(raw_ostream &os, mlir::Block &block) {
+  block.print(os);
+  return os;
+}