diff --git a/lib/CodeGen/MachineFunction.cpp b/lib/CodeGen/MachineFunction.cpp
index d8c2f6a..0a3df78 100644
--- a/lib/CodeGen/MachineFunction.cpp
+++ b/lib/CodeGen/MachineFunction.cpp
@@ -60,7 +60,7 @@
   MFInfo = 0;
   FrameInfo = new (Allocator) MachineFrameInfo(*TM.getFrameLowering());
   if (Fn->hasFnAttr(Attribute::StackAlignment))
-    FrameInfo->setMaxAlignment(Attribute::getStackAlignmentFromAttrs(
+    FrameInfo->ensureMaxAlignment(Attribute::getStackAlignmentFromAttrs(
         Fn->getAttributes().getFnAttributes()));
   ConstantPool = new (Allocator) MachineConstantPool(TM.getTargetData());
   Alignment = TM.getTargetLowering()->getMinFunctionAlignment();