diff --git a/mlir/include/mlir/Interfaces/SideEffectInterfaces.h b/mlir/include/mlir/Interfaces/SideEffectInterfaces.h
--- a/mlir/include/mlir/Interfaces/SideEffectInterfaces.h
+++ b/mlir/include/mlir/Interfaces/SideEffectInterfaces.h
@@ -316,6 +316,8 @@
 /// Return true if the given operation would be dead if unused, and has no side
 /// effects on memory that would prevent erasing. This is equivalent to checking
 /// `isOpTriviallyDead` if `op` was unused.
+///
+/// Note: Terminators and symbols are never considered to be trivially dead.
 bool wouldOpBeTriviallyDead(Operation *op);
 
 /// Returns true if the given operation is free of memory effects.
diff --git a/mlir/lib/Interfaces/SideEffectInterfaces.cpp b/mlir/lib/Interfaces/SideEffectInterfaces.cpp
--- a/mlir/lib/Interfaces/SideEffectInterfaces.cpp
+++ b/mlir/lib/Interfaces/SideEffectInterfaces.cpp
@@ -8,6 +8,7 @@
 
 #include "mlir/Interfaces/SideEffectInterfaces.h"
 
+#include "mlir/IR/SymbolTable.h"
 #include "llvm/ADT/SmallPtrSet.h"
 
 using namespace mlir;
@@ -152,6 +153,8 @@
 bool mlir::wouldOpBeTriviallyDead(Operation *op) {
   if (op->mightHaveTrait<OpTrait::IsTerminator>())
     return false;
+  if (isa<SymbolOpInterface>(op))
+    return false;
   return wouldOpBeTriviallyDeadImpl(op);
 }
 
diff --git a/mlir/test/IR/greedy-pattern-rewriter-driver.mlir b/mlir/test/IR/greedy-pattern-rewriter-driver.mlir
--- a/mlir/test/IR/greedy-pattern-rewriter-driver.mlir
+++ b/mlir/test/IR/greedy-pattern-rewriter-driver.mlir
@@ -24,3 +24,12 @@
   }) {hoist_eligible_ops}: () -> ()
   return
 }
+
+// -----
+
+// There are no patterns in this test that apply to "test.symbol". This test is
+// to ensure that symbols are not getting removed due to being "trivially dead"
+// as part of a greedy rewrite. Symbols are never trivially dead.
+
+// CHECK: "test.symbol"() <{sym_name = "foo"}>
+"test.symbol"() <{sym_name = "foo"}> : () -> ()
diff --git a/mlir/test/Transforms/test-operation-folder-commutative.mlir b/mlir/test/Transforms/test-operation-folder-commutative.mlir
--- a/mlir/test/Transforms/test-operation-folder-commutative.mlir
+++ b/mlir/test/Transforms/test-operation-folder-commutative.mlir
@@ -1,4 +1,4 @@
-// RUN: mlir-opt --pass-pipeline="builtin.module(func.func(test-patterns))" %s | FileCheck %s
+// RUN: mlir-opt --pass-pipeline="builtin.module(test-patterns)" %s | FileCheck %s
 
 // CHECK-LABEL: func @test_reorder_constants_and_match
 func.func @test_reorder_constants_and_match(%arg0 : i32) -> (i32) {
diff --git a/mlir/test/lib/Dialect/Test/TestOps.td b/mlir/test/lib/Dialect/Test/TestOps.td
--- a/mlir/test/lib/Dialect/Test/TestOps.td
+++ b/mlir/test/lib/Dialect/Test/TestOps.td
@@ -106,7 +106,7 @@
 // Test Symbols
 //===----------------------------------------------------------------------===//
 
-def SymbolOp : TEST_Op<"symbol", [Symbol]> {
+def SymbolOp : TEST_Op<"symbol", [NoMemoryEffect, Symbol]> {
   let summary =  "operation which defines a new symbol";
   let arguments = (ins StrAttr:$sym_name,
                        OptionalAttr<StrAttr>:$sym_visibility);
diff --git a/mlir/test/lib/Dialect/Test/TestPatterns.cpp b/mlir/test/lib/Dialect/Test/TestPatterns.cpp
--- a/mlir/test/lib/Dialect/Test/TestPatterns.cpp
+++ b/mlir/test/lib/Dialect/Test/TestPatterns.cpp
@@ -200,7 +200,7 @@
 };
 
 struct TestPatternDriver
-    : public PassWrapper<TestPatternDriver, OperationPass<func::FuncOp>> {
+    : public PassWrapper<TestPatternDriver, OperationPass<ModuleOp>> {
   MLIR_DEFINE_EXPLICIT_INTERNAL_INLINE_TYPE_ID(TestPatternDriver)
 
   TestPatternDriver() = default;