Index: cfe/trunk/lib/Driver/ToolChains/MinGW.cpp
===================================================================
--- cfe/trunk/lib/Driver/ToolChains/MinGW.cpp
+++ cfe/trunk/lib/Driver/ToolChains/MinGW.cpp
@@ -220,8 +220,24 @@
         CmdArgs.push_back("-lssp_nonshared");
         CmdArgs.push_back("-lssp");
       }
-      if (Args.hasArg(options::OPT_fopenmp))
-        CmdArgs.push_back("-lgomp");
+
+      if (Args.hasFlag(options::OPT_fopenmp, options::OPT_fopenmp_EQ,
+                       options::OPT_fno_openmp, false)) {
+        switch (TC.getDriver().getOpenMPRuntime(Args)) {
+        case Driver::OMPRT_OMP:
+          CmdArgs.push_back("-lomp");
+          break;
+        case Driver::OMPRT_IOMP5:
+          CmdArgs.push_back("-liomp5md");
+          break;
+        case Driver::OMPRT_GOMP:
+          CmdArgs.push_back("-lgomp");
+          break;
+        case Driver::OMPRT_Unknown:
+          // Already diagnosed.
+          break;
+        }
+      }
 
       AddLibGCC(Args, CmdArgs);
 
Index: cfe/trunk/test/Driver/fopenmp.c
===================================================================
--- cfe/trunk/test/Driver/fopenmp.c
+++ cfe/trunk/test/Driver/fopenmp.c
@@ -10,6 +10,9 @@
 // RUN: %clang -target x86_64-netbsd -fopenmp=libomp -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-CC1-OPENMP
 // RUN: %clang -target x86_64-netbsd -fopenmp=libgomp -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-CC1-NO-OPENMP
 // RUN: %clang -target x86_64-netbsd -fopenmp=libiomp5 -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-CC1-OPENMP
+// RUN: %clang -target x86_64-windows-gnu -fopenmp=libomp -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-CC1-OPENMP
+// RUN: %clang -target x86_64-windows-gnu -fopenmp=libgomp -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-CC1-NO-OPENMP
+// RUN: %clang -target x86_64-windows-gnu -fopenmp=libiomp5 -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-CC1-OPENMP
 //
 // CHECK-CC1-OPENMP: "-cc1"
 // CHECK-CC1-OPENMP: "-fopenmp"
@@ -49,6 +52,14 @@
 // RUN: %clang -nostdlib -target x86_64-netbsd -fopenmp=libgomp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-NO-GOMP
 // RUN: %clang -nostdlib -target x86_64-netbsd -fopenmp=libiomp5 %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-NO-IOMP5
 //
+// RUN: %clang -target x86_64-windows-gnu -fopenmp=libomp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-OMP
+// RUN: %clang -target x86_64-windows-gnu -fopenmp=libgomp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-GOMP --check-prefix=CHECK-LD-GOMP-NO-RT
+// RUN: %clang -target x86_64-windows-gnu -fopenmp=libiomp5 %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-IOMP5MD
+//
+// RUN: %clang -nostdlib -target x86_64-windows-gnu -fopenmp=libomp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-NO-OMP
+// RUN: %clang -nostdlib -target x86_64-windows-gnu -fopenmp=libgomp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-NO-GOMP
+// RUN: %clang -nostdlib -target x86_64-windows-gnu -fopenmp=libiomp5 %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-NO-IOMP5MD
+//
 // CHECK-LD-OMP: "{{.*}}ld{{(.exe)?}}"
 // CHECK-LD-OMP: "-lomp"
 //
@@ -60,6 +71,9 @@
 // CHECK-LD-IOMP5: "{{.*}}ld{{(.exe)?}}"
 // CHECK-LD-IOMP5: "-liomp5"
 //
+// CHECK-LD-IOMP5MD: "{{.*}}ld{{(.exe)?}}"
+// CHECK-LD-IOMP5MD: "-liomp5md"
+//
 // CHECK-NO-OMP: "{{.*}}ld{{(.exe)?}}"
 // CHECK-NO-OMP-NOT: "-lomp"
 //
@@ -69,6 +83,9 @@
 // CHECK-NO-IOMP5: "{{.*}}ld{{(.exe)?}}"
 // CHECK-NO-IOMP5-NOT: "-liomp5"
 //
+// CHECK-NO-IOMP5MD: "{{.*}}ld{{(.exe)?}}"
+// CHECK-NO-IOMP5MD-NOT: "-liomp5md"
+//
 // We'd like to check that the default is sane, but until we have the ability
 // to *always* semantically analyze OpenMP without always generating runtime
 // calls (in the event of an unsupported runtime), we don't have a good way to
@@ -79,6 +96,10 @@
 // RUN: %clang -target x86_64-darwin -fopenmp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-ANY
 // RUN: %clang -target x86_64-freebsd -fopenmp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-ANY
 // RUN: %clang -target x86_64-netbsd -fopenmp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-ANY
+// RUN: %clang -target x86_64-windows-gnu -fopenmp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-ANYMD
 //
 // CHECK-LD-ANY: "{{.*}}ld{{(.exe)?}}"
 // CHECK-LD-ANY: "-l{{(omp|gomp|iomp5)}}"
+//
+// CHECK-LD-ANYMD: "{{.*}}ld{{(.exe)?}}"
+// CHECK-LD-ANYMD: "-l{{(omp|gomp|iomp5md)}}"