diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td
--- a/clang/include/clang/Basic/DiagnosticGroups.td
+++ b/clang/include/clang/Basic/DiagnosticGroups.td
@@ -1202,5 +1202,8 @@
 These limits can be helpful in limiting code growth through included files.
 
 Setting a token limit of zero means no limit.
+
+Note that the warning is disabled by default, so -Wmax-tokens must be used
+in addition with the pragmas or -fmax-tokens flag to get any warnings.
 }];
 }
diff --git a/clang/include/clang/Basic/DiagnosticParseKinds.td b/clang/include/clang/Basic/DiagnosticParseKinds.td
--- a/clang/include/clang/Basic/DiagnosticParseKinds.td
+++ b/clang/include/clang/Basic/DiagnosticParseKinds.td
@@ -1428,11 +1428,11 @@
 
 def warn_max_tokens : Warning<
   "the number of preprocessor source tokens (%0) exceeds this token limit (%1)">,
-  InGroup<MaxTokens>;
+  InGroup<MaxTokens>, DefaultIgnore;
 
 def warn_max_tokens_total : Warning<
   "the total number of preprocessor source tokens (%0) exceeds the token limit (%1)">,
-  InGroup<MaxTokens>;
+  InGroup<MaxTokens>, DefaultIgnore;
 
 def note_max_tokens_total_override : Note<"total token limit set here">;
 
diff --git a/clang/test/Parser/max-tokens.cpp b/clang/test/Parser/max-tokens.cpp
--- a/clang/test/Parser/max-tokens.cpp
+++ b/clang/test/Parser/max-tokens.cpp
@@ -1,6 +1,6 @@
-// RUN: %clang_cc1 -fsyntax-only -verify %s
-// RUN: %clang_cc1 -fsyntax-only -verify %s -DMAX_TOKENS          -fmax-tokens=2
-// RUN: %clang_cc1 -fsyntax-only -verify %s -DMAX_TOKENS_OVERRIDE -fmax-tokens=9
+// RUN: %clang_cc1 -fsyntax-only -verify %s -Wmax-tokens
+// RUN: %clang_cc1 -fsyntax-only -verify %s -Wmax-tokens -DMAX_TOKENS          -fmax-tokens=2
+// RUN: %clang_cc1 -fsyntax-only -verify %s -Wmax-tokens -DMAX_TOKENS_OVERRIDE -fmax-tokens=9
 
 int x, y, z;