Index: llvm/trunk/lib/IR/Verifier.cpp
===================================================================
--- llvm/trunk/lib/IR/Verifier.cpp
+++ llvm/trunk/lib/IR/Verifier.cpp
@@ -1097,6 +1097,7 @@
     Assert(isa<ConstantAsMetadata>(V) &&
                !isa<Function>(cast<ConstantAsMetadata>(V)->getValue()),
            "invalid global varaible ref", &N, V);
+    visitConstantExprsRecursively(cast<ConstantAsMetadata>(V)->getValue());
   }
   if (auto *Member = N.getRawStaticDataMemberDeclaration()) {
     Assert(isa<DIDerivedType>(Member), "invalid static data member declaration",
@@ -1561,13 +1562,19 @@
     if (const auto *CE = dyn_cast<ConstantExpr>(C))
       visitConstantExpr(CE);
 
+    if (const auto *GV = dyn_cast<GlobalValue>(C)) {
+      // Global Values get visited separately, but we do need to make sure
+      // that the global value is in the correct module
+      Assert(GV->getParent() == M, "Referencing global in another module!",
+             EntryC, M, GV, GV->getParent());
+      continue;
+    }
+
     // Visit all sub-expressions.
     for (const Use &U : C->operands()) {
       const auto *OpC = dyn_cast<Constant>(U);
       if (!OpC)
         continue;
-      if (isa<GlobalValue>(OpC))
-        continue; // Global values get visited separately.
       if (!ConstantExprVisited.insert(OpC).second)
         continue;
       Stack.push_back(OpC);
Index: llvm/trunk/unittests/IR/VerifierTest.cpp
===================================================================
--- llvm/trunk/unittests/IR/VerifierTest.cpp
+++ llvm/trunk/unittests/IR/VerifierTest.cpp
@@ -9,6 +9,7 @@
 
 #include "llvm/IR/Verifier.h"
 #include "llvm/IR/Constants.h"
+#include "llvm/IR/DIBuilder.h"
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/GlobalAlias.h"
@@ -119,7 +120,28 @@
   F3->eraseFromParent();
 }
 
+TEST(VerifierTest, CrossModuleMetadataRef) {
+  LLVMContext &C = getGlobalContext();
+  Module M1("M1", C);
+  Module M2("M2", C);
+  GlobalVariable *newGV =
+      new GlobalVariable(M1, Type::getInt8Ty(C), false,
+                         GlobalVariable::ExternalLinkage, NULL, "Some Global");
+
+  DIBuilder dbuilder(M2);
+  auto CU = dbuilder.createCompileUnit(dwarf::DW_LANG_Julia, "test.jl", ".",
+                                       "unittest", false, "", 0);
+  auto File = dbuilder.createFile("test.jl", ".");
+  auto Ty = dbuilder.createBasicType("Int8", 8, 8, dwarf::DW_ATE_signed);
+  dbuilder.createGlobalVariable(CU, "_SOME_GLOBAL", "_SOME_GLOBAL", File, 1, Ty,
+                                false, newGV);
+  dbuilder.finalize();
 
-
+  std::string Error;
+  raw_string_ostream ErrorOS(Error);
+  EXPECT_TRUE(verifyModule(M2, &ErrorOS));
+  EXPECT_TRUE(StringRef(ErrorOS.str())
+                  .startswith("Referencing global in another module!"));
+}
 }
 }