diff --git a/Makefile b/Makefile
index 460a889..5bd330f 100644
--- a/Makefile
+++ b/Makefile
@@ -5,7 +5,9 @@ CMDSRC= src/cmd.cpp
 TESTSOURCES= tests/test_cheapgmp.cpp
 LDFLAGS=
 TESTLDFLAGS= -laeryn_tests -laeryn_core
-CFLAGS= -c -Wall -std=c++11
+
+# Enable __USE_MISC if you're using clang
+CFLAGS= -c -Wall -std=c++11 # -D__USE_MISC
 CPLUSPLUS= g++
 BINARY=cheapgmp
 CMD=gmpcmd
diff --git a/src/cheapgmp.hpp b/src/cheapgmp.hpp
index 16f8c4f..fed64f1 100644
--- a/src/cheapgmp.hpp
+++ b/src/cheapgmp.hpp
@@ -1,3 +1,4 @@
+#include "compat.hpp"
 #include <memory>
 #include <list>
 #include <algorithm>
diff --git a/src/compat.hpp b/src/compat.hpp
new file mode 100644
index 0000000..63e65cf
--- /dev/null
+++ b/src/compat.hpp
@@ -0,0 +1,6 @@
+#ifdef __USE_MISC
+/* Old compatibility names for C types.  */
+typedef unsigned long int ulong;
+typedef unsigned short int ushort;
+typedef unsigned int uint;
+#endif