Index: lib/Frontend/PrintPreprocessedOutput.cpp
===================================================================
--- lib/Frontend/PrintPreprocessedOutput.cpp
+++ lib/Frontend/PrintPreprocessedOutput.cpp
@@ -588,6 +588,37 @@
     Callbacks->setEmittedDirectiveOnThisLine();
   }
 };
+struct OMPPragmaHandler : public PragmaHandler {
+  const char *Prefix;
+  PrintPPOutputPPCallbacks *Callbacks;
+
+  OMPPragmaHandler(const char *prefix, PrintPPOutputPPCallbacks *callbacks)
+      : Prefix(prefix), Callbacks(callbacks) {}
+  void HandlePragma(Preprocessor &PP, PragmaIntroducerKind Introducer,
+                    Token &PragmaTok) override {
+
+    // The tokens after pragma omp need to be expanded.
+    //
+    //  OpenMP [2.1, Directive format]
+    //  Preprocessing tokens following the #pragma omp are subject to macro
+    //  replacement.
+
+    // Figure out what line we went to and insert the appropriate number of
+    // newline characters.
+    Callbacks->startNewLineIfNeeded();
+    Callbacks->MoveToLine(PragmaTok.getLocation());
+    Callbacks->OS.write(Prefix, strlen(Prefix));
+    // Read and print all of the pragma tokens.
+    while (PragmaTok.isNot(tok::eod)) {
+      if (PragmaTok.hasLeadingSpace())
+        Callbacks->OS << ' ';
+      std::string TokSpell = PP.getSpelling(PragmaTok);
+      Callbacks->OS.write(&TokSpell[0], TokSpell.size());
+      PP.Lex(PragmaTok);
+    }
+    Callbacks->setEmittedDirectiveOnThisLine();
+  }
+};
 } // end anonymous namespace
 
 
@@ -722,6 +753,7 @@
   PP.AddPragmaHandler("GCC", new UnknownPragmaHandler("#pragma GCC",Callbacks));
   PP.AddPragmaHandler("clang",
                       new UnknownPragmaHandler("#pragma clang", Callbacks));
+  PP.AddPragmaHandler("omp", new OMPPragmaHandler("#pragma omp", Callbacks));
 
   PP.addPPCallbacks(std::unique_ptr<PPCallbacks>(Callbacks));
 
Index: test/OpenMP/preprocessor.c
===================================================================
--- /dev/null
+++ test/OpenMP/preprocessor.c
@@ -0,0 +1,30 @@
+// RUN:   %clang -fopenmp -E -o - %s 2>&1 | FileCheck %s
+
+// This is to make sure the pragma name is not expanded!
+#define omp (0xDEADBEEF)
+
+#define N 2
+#define M 1
+
+#define map_to_be_expanded(x) map(tofrom:x)
+#define sched_to_be_expanded(x) schedule(x,N)
+#define reda_to_be_expanded(x) reduction(+:x)
+#define redb_to_be_expanded(x,op) reduction(op:x)
+
+void foo(int *a, int *b) {
+  //CHECK: omp target map(a[0:2]) map(tofrom:b[0:2*1])
+  #pragma omp target map(a[0:N]) map_to_be_expanded(b[0:2*M])
+  {
+    int reda;
+    int redb;
+    //CHECK: omp parallel for schedule(static,2) reduction(+:reda) reduction(*:redb)
+    #pragma omp parallel for sched_to_be_expanded(static) \
+        reda_to_be_expanded(reda) redb_to_be_expanded(redb,*)
+    for (int i = 0; i < N; ++i) {
+      reda += a[i];
+      redb += b[i];
+    }
+    a[0] = reda;
+    b[0] = redb;
+  }
+}