Adding newly required headers

Change-Id: I4c121eaf8fdade8b038fdc696df2d93309d78133
diff --git a/src/class_linker.cc b/src/class_linker.cc
index a72cbbf..ff8e179 100644
--- a/src/class_linker.cc
+++ b/src/class_linker.cc
@@ -2,6 +2,9 @@
 
 #include "class_linker.h"
 
+#include <sys/types.h>
+#include <sys/wait.h>
+
 #include <deque>
 #include <string>
 #include <utility>
diff --git a/src/runtime.cc b/src/runtime.cc
index cfb1b29..a00ebcd 100644
--- a/src/runtime.cc
+++ b/src/runtime.cc
@@ -2,6 +2,8 @@
 
 #include "runtime.h"
 
+#include <signal.h>
+
 #include <cstdio>
 #include <cstdlib>
 #include <limits>
diff --git a/src/thread.cc b/src/thread.cc
index 741727c..92d358c 100644
--- a/src/thread.cc
+++ b/src/thread.cc
@@ -19,6 +19,8 @@
 #include <dynamic_annotations.h>
 #include <pthread.h>
 #include <sys/mman.h>
+#include <sys/resource.h>
+#include <sys/time.h>
 
 #include <algorithm>
 #include <bitset>