Make this compile on Solaris.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@19047 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/llvmc/CompilerDriver.cpp b/tools/llvmc/CompilerDriver.cpp
index f0f6868..6578815 100644
--- a/tools/llvmc/CompilerDriver.cpp
+++ b/tools/llvmc/CompilerDriver.cpp
@@ -21,6 +21,7 @@
 #include "llvm/ADT/SetVector.h"
 #include "llvm/ADT/StringExtras.h"
 #include <iostream>
+#include <alloca.h>
 
 using namespace llvm;