Index: llvm/lib/Transforms/IPO/OpenMPOpt.cpp
===================================================================
--- llvm/lib/Transforms/IPO/OpenMPOpt.cpp
+++ llvm/lib/Transforms/IPO/OpenMPOpt.cpp
@@ -388,6 +388,30 @@
   /// Helper to initialize all runtime function information for those defined in
   /// OpenMPKinds.def.
   void initializeRuntimeFunctions() {
+    // Helper to check the types in the declaration against the expected types.
+    auto CheckTypes = [&](RuntimeFunctionInfo &RFI) {
+      if (!RFI.Declaration)
+        return true;
+
+      Function *F = RFI.Declaration;
+      if (F->getReturnType()->getTypeID() != RFI.ReturnType->getTypeID())
+        return false;
+
+      if (F->arg_size() != RFI.getNumArgs())
+        return false;
+      
+      SmallVector<Type *, 8>::iterator RTFTyIt;
+      RTFTyIt = RFI.ArgumentTypes.begin();
+      for (Argument &Arg : F->args()) {
+        if (Arg.getType()->getTypeID() != (*RTFTyIt)->getTypeID())
+          return false;
+
+        ++RTFTyIt;
+      }
+
+      return true;
+    }; 
+
     // Helper to collect all uses of the decleration in the UsesMap.
     auto CollectUses = [&](RuntimeFunctionInfo &RFI) {
       unsigned NumUses = 0;
@@ -422,6 +446,8 @@
     RFI.ReturnType = _ReturnType;                                              \
     RFI.ArgumentTypes = SmallVector<Type *, 8>({__VA_ARGS__});                 \
     RFI.Declaration = M.getFunction(_Name);                                    \
+    bool TypesMatch = CheckTypes(RFI);                                         \
+    (void)TypesMatch;                                                          \
     unsigned NumUses = CollectUses(RFI);                                       \
     (void)NumUses;                                                             \
     LLVM_DEBUG({                                                               \
@@ -434,7 +460,6 @@
   }
 #include "llvm/Frontend/OpenMP/OMPKinds.def"
 
-    // TODO: We should validate the declaration agains the types we expect.
     // TODO: We should attach the attributes defined in OMPKinds.def.
   }