diff --git a/cache.cxx b/cache.cxx
index 5104f8d..aaba56f 100644
--- a/cache.cxx
+++ b/cache.cxx
@@ -22,6 +22,7 @@ extern "C" {
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <glob.h>
+#include <unistd.h>
 }
 
 using namespace std;
diff --git a/csclient.cxx b/csclient.cxx
index 21f945f..9f8faee 100644
--- a/csclient.cxx
+++ b/csclient.cxx
@@ -24,6 +24,7 @@
 #include <algorithm>
 
 extern "C" {
+#include <unistd.h>
 #include <linux/limits.h>
 #include <sys/time.h>
 #include <glob.h>
diff --git a/session.cxx b/session.cxx
index b322600..2436031 100644
--- a/session.cxx
+++ b/session.cxx
@@ -30,6 +30,7 @@ extern "C" {
 #include <sys/stat.h>
 #include <sys/utsname.h>
 #include <elfutils/libdwfl.h>
+#include <unistd.h>
 }
 
 #if HAVE_NSS
diff --git a/setupdwfl.cxx b/setupdwfl.cxx
index 71814d7..ee1dbd0 100644
--- a/setupdwfl.cxx
+++ b/setupdwfl.cxx
@@ -23,6 +23,7 @@
 extern "C" {
 #include <fnmatch.h>
 #include <stdlib.h>
+#include <unistd.h>
 }
 
 // XXX: also consider adding $HOME/.debug/ for perf build-id-cache
diff --git a/stap-serverd.cxx b/stap-serverd.cxx
index 8ee3b09..9e1345a 100644
--- a/stap-serverd.cxx
+++ b/stap-serverd.cxx
@@ -29,6 +29,7 @@
 #include <map>
 
 extern "C" {
+#include <unistd.h>
 #include <getopt.h>
 #include <wordexp.h>
 #include <glob.h>
diff --git a/translate.cxx b/translate.cxx
index 543c908..9d4c137 100644
--- a/translate.cxx
+++ b/translate.cxx
@@ -5569,7 +5569,7 @@ emit_symbol_data (systemtap_session& s)
 
   ofstream kallsyms_out ((s.tmpdir + "/" + symfile).c_str());
 
-  unwindsym_dump_context ctx = { s, kallsyms_out, 0, ~0, s.unwindsym_modules };
+  unwindsym_dump_context ctx = { s, kallsyms_out, 0, ~0UL, s.unwindsym_modules };
 
   // Micro optimization, mainly to speed up tiny regression tests
   // using just begin probe.