diff --git a/src/DNS_Mgr.cc b/src/DNS_Mgr.cc
index c205b1f829..eee923c76a 100644
--- a/src/DNS_Mgr.cc
+++ b/src/DNS_Mgr.cc
@@ -6,11 +6,11 @@
 
 #include <sys/types.h>
 #include <sys/socket.h>
-#if TIME_WITH_SYS_TIME
+#ifdef TIME_WITH_SYS_TIME
 # include <sys/time.h>
 # include <time.h>
 #else
-# if HAVE_SYS_TIME_H
+# ifdef HAVE_SYS_TIME_H
 #  include <sys/time.h>
 # else
 #  include <time.h>
diff --git a/src/File.cc b/src/File.cc
index d72c67b4ef..d7bc408bdf 100644
--- a/src/File.cc
+++ b/src/File.cc
@@ -5,11 +5,11 @@
 #include "config.h"
 
 #include <sys/types.h>
-#if TIME_WITH_SYS_TIME
+#ifdef TIME_WITH_SYS_TIME
 # include <sys/time.h>
 # include <time.h>
 #else
-# if HAVE_SYS_TIME_H
+# ifdef HAVE_SYS_TIME_H
 #  include <sys/time.h>
 # else
 #  include <time.h>
diff --git a/src/Func.cc b/src/Func.cc
index 0657cfa2c4..5d71be2b0f 100644
--- a/src/Func.cc
+++ b/src/Func.cc
@@ -6,11 +6,11 @@
 
 #include <sys/types.h>
 #include <sys/stat.h>
-#if TIME_WITH_SYS_TIME
+#ifdef TIME_WITH_SYS_TIME
 # include <sys/time.h>
 # include <time.h>
 #else
-# if HAVE_SYS_TIME_H
+# ifdef HAVE_SYS_TIME_H
 #  include <sys/time.h>
 # else
 #  include <time.h>
diff --git a/src/Net.cc b/src/Net.cc
index 73b02aa141..87aa5eb03c 100644
--- a/src/Net.cc
+++ b/src/Net.cc
@@ -5,11 +5,11 @@
 #include "config.h"
 
 #include <sys/types.h>
-#if TIME_WITH_SYS_TIME
+#ifdef TIME_WITH_SYS_TIME
 # include <sys/time.h>
 # include <time.h>
 #else
-# if HAVE_SYS_TIME_H
+# ifdef HAVE_SYS_TIME_H
 #  include <sys/time.h>
 # else
 #  include <time.h>
diff --git a/src/RemoteSerializer.cc b/src/RemoteSerializer.cc
index 203bcd04f5..53429ff548 100644
--- a/src/RemoteSerializer.cc
+++ b/src/RemoteSerializer.cc
@@ -161,11 +161,11 @@
 #include <stdarg.h>
 
 #include "config.h"
-#if TIME_WITH_SYS_TIME
+#ifdef TIME_WITH_SYS_TIME
 # include <sys/time.h>
 # include <time.h>
 #else
-# if HAVE_SYS_TIME_H
+# ifdef HAVE_SYS_TIME_H
 #  include <sys/time.h>
 # else
 #  include <time.h>
diff --git a/src/nb_dns.c b/src/nb_dns.c
index c2092a8b5b..5033aadad4 100644
--- a/src/nb_dns.c
+++ b/src/nb_dns.c
@@ -103,7 +103,7 @@ static int _nb_dns_cmpsockaddr(struct sockaddr *, struct sockaddr *, char *);
 static char *
 my_strerror(int errnum)
 {
-#if HAVE_STRERROR
+#ifdef HAVE_STRERROR
 	extern char *strerror(int);
 	return strerror(errnum);
 #else
diff --git a/src/util.cc b/src/util.cc
index 0e49600cc2..d24e7ee7cb 100644
--- a/src/util.cc
+++ b/src/util.cc
@@ -4,11 +4,11 @@
 
 #include "config.h"
 
-#if TIME_WITH_SYS_TIME
+#ifdef TIME_WITH_SYS_TIME
 # include <sys/time.h>
 # include <time.h>
 #else
-# if HAVE_SYS_TIME_H
+# ifdef HAVE_SYS_TIME_H
 #  include <sys/time.h>
 # else
 #  include <time.h>