diff --git a/controls/button.c b/controls/button.c
index 13b56899bda..3da2a9a74c3 100644
--- a/controls/button.c
+++ b/controls/button.c
@@ -5,6 +5,7 @@
  * Copyright (C) 1994 Alexandre Julliard
  */
 
+#include <string.h>
 #include "win.h"
 #include "button.h"
 #include "winuser.h"
diff --git a/controls/edit.c b/controls/edit.c
index f0d83f06501..b53dde0a469 100644
--- a/controls/edit.c
+++ b/controls/edit.c
@@ -11,6 +11,7 @@
  *	please read EDIT.TODO (and update it when you change things)
  */
 
+#include <string.h>
 #include "winnt.h"
 #include "win.h"
 #include "wine/winbase16.h"
diff --git a/controls/widgets.c b/controls/widgets.c
index 51c6250dbb3..fc409afd88d 100644
--- a/controls/widgets.c
+++ b/controls/widgets.c
@@ -4,6 +4,7 @@
  * Copyright 1993 Alexandre Julliard
  */
 
+#include <string.h>
 #include <assert.h>
 
 #include "win.h"
diff --git a/dlls/advapi32/advapi.c b/dlls/advapi32/advapi.c
index f73c84889d6..2e8691034df 100644
--- a/dlls/advapi32/advapi.c
+++ b/dlls/advapi32/advapi.c
@@ -5,6 +5,7 @@
  */
 
 #include <unistd.h>
+#include <string.h>
 
 #include "wintypes.h"
 #include "winerror.h"
diff --git a/dlls/advapi32/security.c b/dlls/advapi32/security.c
index 6d46d392257..de7b42a3121 100644
--- a/dlls/advapi32/security.c
+++ b/dlls/advapi32/security.c
@@ -1,6 +1,8 @@
 /*
  * dlls/advapi32/security.c
  */
+#include <string.h>
+
 #include "wintypes.h"
 #include "winreg.h"
 #include "winerror.h"
diff --git a/dlls/comctl32/header.c b/dlls/comctl32/header.c
index 253cc41c226..a570378b719 100644
--- a/dlls/comctl32/header.c
+++ b/dlls/comctl32/header.c
@@ -19,6 +19,8 @@
  *   - Little flaw when drawing a bitmap on the right side of the text.
  */
 
+#include <string.h>
+
 #include "commctrl.h"
 #include "win.h"
 #include "header.h"
diff --git a/dlls/comctl32/rebar.c b/dlls/comctl32/rebar.c
index 32b3c1bf8c0..68b82b0f445 100644
--- a/dlls/comctl32/rebar.c
+++ b/dlls/comctl32/rebar.c
@@ -18,6 +18,8 @@
  *   - All notifications.
  */
 
+#include <string.h>
+
 #include "commctrl.h"
 #include "rebar.h"
 #include "win.h"
diff --git a/dlls/comctl32/tab.c b/dlls/comctl32/tab.c
index 06ad3687b96..0db78f69dae 100644
--- a/dlls/comctl32/tab.c
+++ b/dlls/comctl32/tab.c
@@ -13,6 +13,8 @@
  *
  */
 
+#include <string.h>
+
 #include "commctrl.h"
 #include "tab.h"
 #include "win.h"
diff --git a/dlls/comctl32/toolbar.c b/dlls/comctl32/toolbar.c
index 37f0d642ad0..2b272beb285 100644
--- a/dlls/comctl32/toolbar.c
+++ b/dlls/comctl32/toolbar.c
@@ -25,6 +25,8 @@
  *   - Microsofts controlspy examples.
  */
 
+#include <string.h>
+
 #include "commctrl.h"
 #include "sysmetrics.h"
 #include "cache.h"
diff --git a/dlls/comctl32/tooltips.c b/dlls/comctl32/tooltips.c
index d5b756defd6..ed1590b9ec4 100644
--- a/dlls/comctl32/tooltips.c
+++ b/dlls/comctl32/tooltips.c
@@ -13,6 +13,7 @@
  *     curtool.exe, deltool.exe, enumtools.exe, getinfo.exe, getiptxt.exe,
  *     hittest.exe, needtext.exe, newrect.exe, updtext.exe and winfrpt.exe.
  */
+#include <string.h>
 
 #include "commctrl.h"
 #include "tooltips.h"
diff --git a/dlls/comctl32/updown.c b/dlls/comctl32/updown.c
index 25a9ac86168..36816a2a6a0 100644
--- a/dlls/comctl32/updown.c
+++ b/dlls/comctl32/updown.c
@@ -30,6 +30,8 @@
  */
 
 #include <stdlib.h>
+#include <string.h>
+
 #include "commctrl.h"
 #include "winnls.h"
 #include "updown.h"
diff --git a/dlls/shell32/contmenu.c b/dlls/shell32/contmenu.c
index 14f79121ed0..5660a1ccba3 100644
--- a/dlls/shell32/contmenu.c
+++ b/dlls/shell32/contmenu.c
@@ -3,6 +3,8 @@
  *
  *	Copyright 1998	Juergen Schmied <juergen.schmied@metronet.de>
  */
+#include <string.h>
+
 #include "winerror.h"
 #include "debug.h"
 
diff --git a/dlls/shell32/dataobject.c b/dlls/shell32/dataobject.c
index d43de0888dd..b00da1405cd 100644
--- a/dlls/shell32/dataobject.c
+++ b/dlls/shell32/dataobject.c
@@ -5,6 +5,8 @@
  *
  *	Copyright 1998	<juergen.schmied@metronet.de>
  */
+#include <string.h>
+
 #include "debug.h"
 #include "wintypes.h"
 #include "wine/obj_base.h"
diff --git a/graphics/path.c b/graphics/path.c
index bf6e8df888d..290ddcdcbf5 100644
--- a/graphics/path.c
+++ b/graphics/path.c
@@ -7,6 +7,7 @@
 #include <assert.h>
 #include <malloc.h>
 #include <math.h>
+#include <string.h>
 
 #include "winbase.h"
 #include "wingdi.h"
diff --git a/graphics/psdrv/init.c b/graphics/psdrv/init.c
index 23481468362..957709b2e4d 100644
--- a/graphics/psdrv/init.c
+++ b/graphics/psdrv/init.c
@@ -4,6 +4,7 @@
  *	Copyright 1998 Huw D M Davies
  *
  */
+#include <string.h>
 
 #include "gdi.h"
 #include "psdrv.h"
diff --git a/tools/wrc/newstruc.c b/tools/wrc/newstruc.c
index 05d9ee066f4..509d3900d43 100644
--- a/tools/wrc/newstruc.c
+++ b/tools/wrc/newstruc.c
@@ -8,6 +8,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <assert.h>
 
 #include <config.h>