diff --git a/include/Support/Alloca.h b/include/Support/Alloca.h
new file mode 100644
index 00000000000..3c163ed0d66
--- /dev/null
+++ b/include/Support/Alloca.h
@@ -0,0 +1,30 @@
+//===-- include/Support/Alloca.h - Support for alloca header -----*- C++ -*--=//
+//
+// Some platforms do not have alloca.h; others do. You can include this
+// file instead of <alloca.h> and it will include <alloca.h> on the platforms
+// that require you to do so to use alloca().
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_ALLOCA_H
+#define LLVM_SUPPORT_ALLOCA_H
+
+// TODO: Determine HAVE_ALLOCA_H based on autoconf results.
+// The following method is too brittle.
+#if defined(HAVE_ALLOCA_H)
+#undef HAVE_ALLOCA_H
+#endif
+
+#if defined(__linux__)
+#define HAVE_ALLOCA_H 1
+#elif defined(__sparc__)
+#define HAVE_ALLOCA_H 1
+#elif defined(__FreeBSD__)
+// not defined here
+#endif
+
+#if HAVE_ALLOCA_H
+#include <alloca.h>
+#endif
+
+#endif  /* LLVM_SUPPORT_ALLOCA_H */
diff --git a/lib/CodeGen/InstrSelection/InstrForest.cpp b/lib/CodeGen/InstrSelection/InstrForest.cpp
index c33faec9a04..5afa1daccd8 100644
--- a/lib/CodeGen/InstrSelection/InstrForest.cpp
+++ b/lib/CodeGen/InstrSelection/InstrForest.cpp
@@ -21,7 +21,7 @@
 #include "llvm/Type.h"
 #include "llvm/CodeGen/MachineInstr.h"
 #include "Support/STLExtras.h"
-#include <alloca.h>
+#include "Support/Alloca.h"
 using std::cerr;
 using std::vector;
 
diff --git a/lib/Support/SystemUtils.cpp b/lib/Support/SystemUtils.cpp
index 034c141f794..c88a516e9f3 100644
--- a/lib/Support/SystemUtils.cpp
+++ b/lib/Support/SystemUtils.cpp
@@ -10,7 +10,7 @@
 #include <fstream>
 #include <iostream>
 #include <cstdlib>
-#include <alloca.h>
+#include "Support/Alloca.h"
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
diff --git a/lib/Target/SparcV9/InstrSelection/InstrForest.cpp b/lib/Target/SparcV9/InstrSelection/InstrForest.cpp
index c33faec9a04..5afa1daccd8 100644
--- a/lib/Target/SparcV9/InstrSelection/InstrForest.cpp
+++ b/lib/Target/SparcV9/InstrSelection/InstrForest.cpp
@@ -21,7 +21,7 @@
 #include "llvm/Type.h"
 #include "llvm/CodeGen/MachineInstr.h"
 #include "Support/STLExtras.h"
-#include <alloca.h>
+#include "Support/Alloca.h"
 using std::cerr;
 using std::vector;
 
diff --git a/lib/Target/X86/X86CodeEmitter.cpp b/lib/Target/X86/X86CodeEmitter.cpp
index 45d0b8c547e..bfb4aaa9514 100644
--- a/lib/Target/X86/X86CodeEmitter.cpp
+++ b/lib/Target/X86/X86CodeEmitter.cpp
@@ -13,7 +13,7 @@
 #include "llvm/CodeGen/MachineInstr.h"
 #include "llvm/Value.h"
 #include "Support/Statistic.h"
-#include <alloca.h>
+#include "Support/Alloca.h"
 
 namespace {
   Statistic<>
diff --git a/support/lib/Support/SystemUtils.cpp b/support/lib/Support/SystemUtils.cpp
index 034c141f794..c88a516e9f3 100644
--- a/support/lib/Support/SystemUtils.cpp
+++ b/support/lib/Support/SystemUtils.cpp
@@ -10,7 +10,7 @@
 #include <fstream>
 #include <iostream>
 #include <cstdlib>
-#include <alloca.h>
+#include "Support/Alloca.h"
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
diff --git a/tools/bugpoint/SystemUtils.cpp b/tools/bugpoint/SystemUtils.cpp
index 034c141f794..c88a516e9f3 100644
--- a/tools/bugpoint/SystemUtils.cpp
+++ b/tools/bugpoint/SystemUtils.cpp
@@ -10,7 +10,7 @@
 #include <fstream>
 #include <iostream>
 #include <cstdlib>
-#include <alloca.h>
+#include "Support/Alloca.h"
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>