Index: lib/Target/ARM/ARMISelLowering.cpp
===================================================================
--- lib/Target/ARM/ARMISelLowering.cpp
+++ lib/Target/ARM/ARMISelLowering.cpp
@@ -1645,8 +1645,9 @@
   bool isLocalARMFunc = false;
   ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
 
-  if (EnableARMLongCalls) {
-    assert (getTargetMachine().getRelocationModel() == Reloc::Static
+  if (EnableARMLongCalls || Subtarget->isTargetWindows()) {
+    assert ((getTargetMachine().getRelocationModel() == Reloc::Static ||
+             Subtarget->isTargetWindows())
             && "long-calls with non-static relocation model!");
     // Handle a global address or an external symbol. If it's not one of
     // those, the target's already in a register, so we don't need to do
Index: test/CodeGen/ARM/Windows/calls.ll
===================================================================
--- /dev/null
+++ test/CodeGen/ARM/Windows/calls.ll
@@ -0,0 +1,36 @@
+; RUN: llc -mtriple=thumbv7-windows -mcpu=cortex-a9 -o - %s | FileCheck %s
+
+declare void @external()
+
+define void @internal() nounwind {
+entry:
+  ret void
+}
+
+define void @call_external() nounwind {
+entry:
+  tail call void @external()
+  ret void
+}
+
+define void @call_internal() nounwind {
+entry:
+  tail call void @internal()
+  ret void
+}
+
+; CHECK: call_external:
+; CHECK: 	ldr	r0, .L[[CPI:[^ ]*]]
+; CHECK: 	bx	r0
+; CHECK: .align 2
+; CHECK: .L[[CPI]]
+; CHECK: 	.long external
+
+; CHECK: call_internal
+; CHECK: 	ldr	r0, .L[[CPI:[^ ]*]]
+; FIXME: relax this to a bl function
+; CHECK: 	bx	r0
+; CHECK: .align 2
+; CHECK: .L[[CPI]]
+; CHECK: 	.long internal
+