diff --git a/tools/opt/opt.cpp b/tools/opt/opt.cpp
index 4eca3084257..64b554cea4a 100644
--- a/tools/opt/opt.cpp
+++ b/tools/opt/opt.cpp
@@ -267,7 +267,8 @@ void AddStandardCompilePasses(PassManager &PM) {
   addPass(PM, createTailDuplicationPass());      // Simplify cfg by copying code
   addPass(PM, createInstructionCombiningPass()); // Cleanup for scalarrepl.
   addPass(PM, createCFGSimplificationPass());    // Merge & remove BBs
-  addPass(PM, createScalarReplAggregatesPass()); // Break up aggregate allocas
+  // FIXME: Temporary!
+  addPass(PM, createScalarReplAggregatesPass(512)); // Break up aggregate allocas
   addPass(PM, createInstructionCombiningPass()); // Combine silly seq's
   addPass(PM, createCondPropagationPass());      // Propagate conditionals