diff --git a/flang/lib/Frontend/FrontendActions.cpp b/flang/lib/Frontend/FrontendActions.cpp
--- a/flang/lib/Frontend/FrontendActions.cpp
+++ b/flang/lib/Frontend/FrontendActions.cpp
@@ -34,6 +34,7 @@
 #include "mlir/IR/Dialect.h"
 #include "mlir/Parser/Parser.h"
 #include "mlir/Pass/PassManager.h"
+#include "mlir/Support/LLVM.h"
 #include "mlir/Target/LLVMIR/ModuleTranslation.h"
 #include "clang/Basic/Diagnostic.h"
 #include "clang/Basic/DiagnosticFrontend.h"
@@ -564,11 +565,14 @@
 void CodeGenAction::setUpTargetMachine() {
   CompilerInstance &ci = this->getInstance();
 
-  // Set the triple based on the CompilerInvocation set-up
   const std::string &theTriple = ci.getInvocation().getTargetOpts().triple;
-  if (llvmModule->getTargetTriple() != theTriple) {
-    ci.getDiagnostics().Report(clang::diag::warn_fe_override_module)
-        << theTriple;
+
+  // Set the triple based on the CompilerInvocation set-up
+  if (llvmModule) {
+    if (llvmModule->getTargetTriple() != theTriple) {
+      ci.getDiagnostics().Report(clang::diag::warn_fe_override_module)
+          << theTriple;
+    }
     llvmModule->setTargetTriple(theTriple);
   }
 
@@ -697,6 +701,13 @@
   mpm.run(*llvmModule, mam);
 }
 
+static void setMLIRDataLayout(mlir::ModuleOp &mlirModule,
+                              const llvm::DataLayout &dl) {
+  mlirModule->setAttr(mlir::LLVM::LLVMDialect::getDataLayoutAttrName(),
+                      mlir::StringAttr::get(mlirModule.getContext(),
+                                            dl.getStringRepresentation()));
+}
+
 void CodeGenAction::executeAction() {
   CompilerInstance &ci = this->getInstance();
 
@@ -728,12 +739,20 @@
     mlirModule->print(ci.isOutputStreamNull() ? *os : ci.getOutputStream());
     return;
   }
+  setUpTargetMachine();
+  if (mlirModule) {
+    const llvm::DataLayout &dl = tm->createDataLayout();
+    setMLIRDataLayout(*mlirModule, dl);
+  }
 
   // Generate an LLVM module if it's not already present (it will already be
   // present if the input file is an LLVM IR/BC file).
   if (!llvmModule)
     generateLLVMIR();
 
+  if (llvmModule->getDataLayout().isDefault()) {
+    llvmModule->setDataLayout(tm->createDataLayout());
+  }
   // Run LLVM's middle-end (i.e. the optimizer).
   runOptimizationPipeline(*os);
 
@@ -743,9 +762,6 @@
     return;
   }
 
-  setUpTargetMachine();
-  llvmModule->setDataLayout(tm->createDataLayout());
-
   if (action == BackendActionTy::Backend_EmitBC) {
     // This action has effectively been completed in runOptimizationPipeline.
     return;
diff --git a/flang/test/Driver/emit-llvm.f90 b/flang/test/Driver/emit-llvm.f90
--- a/flang/test/Driver/emit-llvm.f90
+++ b/flang/test/Driver/emit-llvm.f90
@@ -6,6 +6,7 @@
 ! RUN: %flang_fc1 -emit-llvm %s -o - | FileCheck %s
 
 ! CHECK: ; ModuleID = 'FIRModule'
+! CHECK: target datalayout =
 ! CHECK: define void @_QQmain()
 ! CHECK-NEXT:  ret void
 ! CHECK-NEXT: }
diff --git a/flang/test/Driver/pic-flags.f90 b/flang/test/Driver/pic-flags.f90
--- a/flang/test/Driver/pic-flags.f90
+++ b/flang/test/Driver/pic-flags.f90
@@ -1,3 +1,4 @@
+! REQUIRES: aarch64-registered-target && x86-registered-target && arm-registered-target
 ! RUN: %flang -v -S -emit-llvm -o - %s --target=aarch64-linux-gnu -fno-pie 2>&1 | FileCheck %s --check-prefixes=CHECK,CHECK-STATIC,CHECK-STATIC-IR
 
 ! RUN: %flang -v -S -emit-llvm -o - %s --target=aarch64-linux-gnu 2>&1 | FileCheck %s --check-prefixes=CHECK,CHECK-PIE-LEVEL2,CHECK-PIE-LEVEL2-IR
@@ -14,7 +15,6 @@
 ! RUN: %flang -v -### -o - %s --target=arm-none-eabi -frwpi 2>&1 | FileCheck %s --check-prefixes=CHECK,CHECK-RWPI
 ! RUN: %flang -v -### -o - %s --target=arm-none-eabi -fropi -frwpi 2>&1 | FileCheck %s --check-prefixes=CHECK,CHECK-ROPI-RWPI
 
-
 ! CHECK: -fc1
 
 
diff --git a/flang/unittests/Frontend/FrontendActionTest.cpp b/flang/unittests/Frontend/FrontendActionTest.cpp
--- a/flang/unittests/Frontend/FrontendActionTest.cpp
+++ b/flang/unittests/Frontend/FrontendActionTest.cpp
@@ -178,6 +178,11 @@
   compInst.getInvocation().getTargetOpts().triple =
       llvm::Triple::normalize(llvm::sys::getDefaultTargetTriple());
 
+  // Initialise LLVM backend
+  llvm::InitializeAllTargets();
+  llvm::InitializeAllTargetMCs();
+  llvm::InitializeAllAsmPrinters();
+
   // Set-up the output stream. We are using output buffer wrapped as an output
   // stream, as opposed to an actual file (or a file descriptor).
   llvm::SmallVector<char> outputFileBuffer;