diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index 11ff6bf..16b110f 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -2391,8 +2391,9 @@
           // In case of tail call optimization mark all arguments mutable. Since they
           // could be overwritten by lowering of arguments in case of a tail call.
           if (Flags.isByVal()) {
-            int FI = MFI->CreateFixedObject(Flags.getByValSize(),
-                                            VA.getLocMemOffset(), false);
+            unsigned Bytes = Flags.getByValSize();
+            if (Bytes == 0) Bytes = 1; // Don't create zero-sized stack objects.
+            int FI = MFI->CreateFixedObject(Bytes, VA.getLocMemOffset(), false);
             InVals.push_back(DAG.getFrameIndex(FI, getPointerTy()));
           } else {
             int FI = MFI->CreateFixedObject(VA.getLocVT().getSizeInBits()/8,
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 7d301e5..cd1d201 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -1639,8 +1639,9 @@
   // In case of tail call optimization mark all arguments mutable. Since they
   // could be overwritten by lowering of arguments in case of a tail call.
   if (Flags.isByVal()) {
-    int FI = MFI->CreateFixedObject(Flags.getByValSize(),
-                                    VA.getLocMemOffset(), isImmutable);
+    unsigned Bytes = Flags.getByValSize();
+    if (Bytes == 0) Bytes = 1; // Don't create zero-sized stack objects.
+    int FI = MFI->CreateFixedObject(Bytes, VA.getLocMemOffset(), isImmutable);
     return DAG.getFrameIndex(FI, getPointerTy());
   } else {
     int FI = MFI->CreateFixedObject(ValVT.getSizeInBits()/8,