Index: include/clang/ASTMatchers/ASTMatchers.h
===================================================================
--- include/clang/ASTMatchers/ASTMatchers.h
+++ include/clang/ASTMatchers/ASTMatchers.h
@@ -2709,6 +2709,19 @@
   return Node.isDeleted();
 }
 
+/// \brief Matches constexpr function declarations.
+///
+/// Given:
+/// \code
+///   int foo();
+///   constexpr int bar();
+/// \endcode
+/// functionDecl(isConstexpr())
+///   matches the declaration of bar, but not foo.
+AST_MATCHER(FunctionDecl, isConstexpr) {
+  return Node.isConstexpr();
+}
+
 /// \brief Matches the condition expression of an if statement, for loop,
 /// or conditional operator.
 ///
Index: unittests/ASTMatchers/ASTMatchersTest.cpp
===================================================================
--- unittests/ASTMatchers/ASTMatchersTest.cpp
+++ unittests/ASTMatchers/ASTMatchersTest.cpp
@@ -1595,6 +1595,13 @@
                       functionDecl(hasName("Func"), isDeleted())));
 }
 
+TEST(isConstexpr, MatchesConstexprFunctionDeclarations) {
+  EXPECT_TRUE(notMatches("int foo();",
+                      functionDecl(hasName("foo"), isConstexpr())));
+  EXPECT_TRUE(matches("constexpr int bar();",
+                      functionDecl(hasName("bar"), isConstexpr())));
+}
+
 TEST(HasAnyParameter, DoesntMatchIfInnerMatcherDoesntMatch) {
   EXPECT_TRUE(notMatches("class Y {}; class X { void x(int) {} };",
       methodDecl(hasAnyParameter(hasType(recordDecl(hasName("X")))))));