Index: include/llvm/Support/FileCheck.h
===================================================================
--- include/llvm/Support/FileCheck.h
+++ include/llvm/Support/FileCheck.h
@@ -35,6 +35,7 @@
   bool AllowDeprecatedDagOverlap = false;
   bool Verbose = false;
   bool VerboseVerbose = false;
+  bool Warn = false;
 };
 
 
Index: lib/Support/FileCheck.cpp
===================================================================
--- lib/Support/FileCheck.cpp
+++ lib/Support/FileCheck.cpp
@@ -25,6 +25,14 @@
 
 using namespace llvm;
 
+static void PrintWarningInRange(SMRange MatchRange, const SourceMgr &SM,
+                                const Twine &Msg,
+                                const FileCheckRequest &Req) {
+  if (!Req.Warn)
+    return;
+  SM.PrintMessage(MatchRange.Start, SourceMgr::DK_Warning, Msg, {MatchRange});
+}
+
 /// Parses the given string into the Pattern.
 ///
 /// \p Prefix provides which prefix is being matched, \p SM provides the
@@ -1214,14 +1222,13 @@
         MatchRanges.insert(MI, M);
         break;
       }
-      if (Req.VerboseVerbose) {
-        SMLoc OldStart = SMLoc::getFromPointer(Buffer.data() + MI->Pos);
-        SMLoc OldEnd = SMLoc::getFromPointer(Buffer.data() + MI->End);
-        SMRange OldRange(OldStart, OldEnd);
-        SM.PrintMessage(OldStart, SourceMgr::DK_Note,
-                        "match discarded, overlaps earlier DAG match here",
-                        {OldRange});
-      }
+
+      SMLoc OldStart = SMLoc::getFromPointer(Buffer.data() + MI->Pos);
+      SMLoc OldEnd = SMLoc::getFromPointer(Buffer.data() + MI->End);
+      SMRange OldRange(OldStart, OldEnd);
+      PrintWarningInRange(OldRange, SM, "match discarded, overlaps earlier "
+                                        "DAG match here", Req);
+
       MatchPos = MI->End;
     }
     if (!Req.VerboseVerbose)
Index: test/FileCheck/check-overlap-warning.txt
===================================================================
--- /dev/null
+++ test/FileCheck/check-overlap-warning.txt
@@ -0,0 +1,12 @@
+; RUN: FileCheck -warn -input-file %s %s 2>&1 | FileCheck -check-prefix=WARNING %s
+
+hello world
+hello world
+
+; CHECK-DAG: hello world 
+; CHECK-DAG: hello world 
+
+; WARNING:       warning: match discarded, overlaps earlier DAG match here
+; WARNING-NEXT:  hello world
+; WARNING-NEXT:  ^~~~~~~~~~~
+
Index: test/FileCheck/verbose.txt
===================================================================
--- test/FileCheck/verbose.txt
+++ test/FileCheck/verbose.txt
@@ -75,16 +75,6 @@
 VV-NEXT: verbose.txt:[[@LINE-15]]:4: note: found here
 VV-NEXT: {{^abcdef$}}
 VV-NEXT: {{^   \^~~$}}
-VV-NEXT: verbose.txt:[[@LINE-18]]:1: note: match discarded, overlaps earlier DAG match here
-VV-NEXT: {{^}}abcdef{{$}}
-VV-NEXT: {{^}}^~~~~~{{$}}
-
-V-NEXT: verbose.txt:[[@LINE-19]]:12: remark: {{C}}HECK-DAG: expected string found in input
-V-NEXT: {{C}}HECK-DAG: def
-V-NEXT:  {{^           \^$}}
-V-NEXT: verbose.txt:[[@LINE-24]]:4: note: found here
-V-NEXT: {{^abcdef$}}
-V-NEXT: {{^   \^~~$}}
 
 xyz
 CHECK: xyz
Index: utils/FileCheck/FileCheck.cpp
===================================================================
--- utils/FileCheck/FileCheck.cpp
+++ utils/FileCheck/FileCheck.cpp
@@ -85,6 +85,10 @@
     "vv", cl::init(false),
     cl::desc("Print information helpful in diagnosing internal FileCheck\n"
              "issues.  Implies -v.\n"));
+
+static cl::opt<bool> Warn("warn", cl::init(false),
+                          cl::desc("Print warning messages.\n"));
+
 static const char * DumpInputEnv = "FILECHECK_DUMP_INPUT_ON_FAILURE";
 
 static cl::opt<bool> DumpInputOnFailure(
@@ -130,6 +134,7 @@
   Req.AllowEmptyInput = AllowEmptyInput;
   Req.EnableVarScope = EnableVarScope;
   Req.AllowDeprecatedDagOverlap = AllowDeprecatedDagOverlap;
+  Req.Warn = Warn;
   Req.Verbose = Verbose;
   Req.VerboseVerbose = VerboseVerbose;
   Req.NoCanonicalizeWhiteSpace = NoCanonicalizeWhiteSpace;