diff --git a/lib/Target/PowerPC/PPCRegisterInfo.cpp b/lib/Target/PowerPC/PPCRegisterInfo.cpp
index cc69fb5206f..113c9fd82b2 100644
--- a/lib/Target/PowerPC/PPCRegisterInfo.cpp
+++ b/lib/Target/PowerPC/PPCRegisterInfo.cpp
@@ -449,8 +449,8 @@ void PPCRegisterInfo::lowerDynamicAlloc(MachineBasicBlock::iterator II,
   // Get stack alignments.
   unsigned TargetAlign = MF.getTarget().getFrameInfo()->getStackAlignment();
   unsigned MaxAlign = MFI->getMaxAlignment();
-  assert(MaxAlign <= TargetAlign &&
-         "Dynamic alloca with large aligns not supported");
+  if (MaxAlign > TargetAlign)
+    report_fatal_error("Dynamic alloca with large aligns not supported");
 
   // Determine the previous frame's address.  If FrameSize can't be
   // represented as 16 bits or we need special alignment, then we load the
diff --git a/test/FrontendC/vla-1.c b/test/FrontendC/vla-1.c
index c6c58f6cc36..77f78a5e3af 100644
--- a/test/FrontendC/vla-1.c
+++ b/test/FrontendC/vla-1.c
@@ -1,4 +1,6 @@
 // RUN: %llvmgcc_only -std=gnu99 %s -S |& grep {warning: alignment for}
+// ppc does not support this feature, and gets a fatal error at runtime.
+// XFAIL: powerpc
 
 int foo(int a)
 {