diff --git a/ext/annodex/gstannodex.c b/ext/annodex/gstannodex.c
index 05e10c8e44..789091cfe5 100644
--- a/ext/annodex/gstannodex.c
+++ b/ext/annodex/gstannodex.c
@@ -26,6 +26,8 @@
 #endif
 
 #include <math.h>
+#include <string.h>
+
 #include <gst/tag/tag.h>
 #include "gstannodex.h"
 #include "gstcmmlparser.h"
diff --git a/gst/audiofx/audiochebband.c b/gst/audiofx/audiochebband.c
index caa40cef02..f0d2e34f05 100644
--- a/gst/audiofx/audiochebband.c
+++ b/gst/audiofx/audiochebband.c
@@ -70,6 +70,8 @@
 #include "config.h"
 #endif
 
+#include <string.h>
+
 #include <gst/gst.h>
 #include <gst/base/gstbasetransform.h>
 #include <gst/audio/audio.h>
diff --git a/gst/audiofx/audiocheblimit.c b/gst/audiofx/audiocheblimit.c
index 8905cbfff5..250857ec0a 100644
--- a/gst/audiofx/audiocheblimit.c
+++ b/gst/audiofx/audiocheblimit.c
@@ -66,6 +66,8 @@
 #include "config.h"
 #endif
 
+#include <string.h>
+
 #include <gst/gst.h>
 #include <gst/base/gstbasetransform.h>
 #include <gst/audio/audio.h>
diff --git a/gst/audiofx/audiofxbaseiirfilter.c b/gst/audiofx/audiofxbaseiirfilter.c
index 0b8c0883d1..ee2f88dff0 100644
--- a/gst/audiofx/audiofxbaseiirfilter.c
+++ b/gst/audiofx/audiofxbaseiirfilter.c
@@ -22,6 +22,8 @@
 #include "config.h"
 #endif
 
+#include <string.h>
+
 #include <gst/gst.h>
 #include <gst/base/gstbasetransform.h>
 #include <gst/audio/audio.h>
diff --git a/gst/audiofx/audiopanorama.c b/gst/audiofx/audiopanorama.c
index 133bb77d33..0802c4c2ed 100644
--- a/gst/audiofx/audiopanorama.c
+++ b/gst/audiofx/audiopanorama.c
@@ -40,6 +40,8 @@
 #include "config.h"
 #endif
 
+#include <string.h>
+
 #include <gst/gst.h>
 #include <gst/base/gstbasetransform.h>
 
diff --git a/gst/equalizer/gstiirequalizer.c b/gst/equalizer/gstiirequalizer.c
index b93d1b5148..53286df380 100644
--- a/gst/equalizer/gstiirequalizer.c
+++ b/gst/equalizer/gstiirequalizer.c
@@ -24,6 +24,7 @@
 #endif
 
 #include <math.h>
+#include <stdio.h>
 #include <string.h>
 
 #include "gstiirequalizer.h"