diff --git a/common/pixman-region.c b/common/pixman-region.c
index d572c4f4..bb3d3714 100644
--- a/common/pixman-region.c
+++ b/common/pixman-region.c
@@ -63,8 +63,11 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-#if defined(HAVE_CONFIG_H)
-#include <config_ac.h>
+#ifndef PIXMAN_REGION_MAX
+#error "This file should be #included from pixman-region16.c, not compiled directly"
+#endif
+#ifndef CONFIG_AC_H
+#error "config_ac.h not visible in pixman-region.c"
 #endif
 
 #define PIXREGION_NIL(reg) ((reg)->data && !(reg)->data->numRects)
diff --git a/genkeymap/evdev-map.c b/genkeymap/evdev-map.c
index 9a9bfd32..1817ab08 100644
--- a/genkeymap/evdev-map.c
+++ b/genkeymap/evdev-map.c
@@ -22,6 +22,10 @@
  * xfree86(base)->evdev keycode mapping
  */
 
+#if defined(HAVE_CONFIG_H)
+#include <config_ac.h>
+#endif
+
 int xfree86_to_evdev[137 - 8 + 1] =
 {
     /* MDSW */ 203,
diff --git a/libipm/libipm.h b/libipm/libipm.h
index fb75fc97..4d6bef27 100644
--- a/libipm/libipm.h
+++ b/libipm/libipm.h
@@ -26,10 +26,6 @@
 #if !defined(LIBIPM_H)
 #define LIBIPM_H
 
-#if defined(HAVE_CONFIG_H)
-#include <config_ac.h>
-#endif
-
 #include "arch.h"
 #include "libipm_facilities.h"
 
diff --git a/sesman/chansrv/pcsc/wrapper/winscard.c b/sesman/chansrv/pcsc/wrapper/winscard.c
index 7866f310..a8287010 100644
--- a/sesman/chansrv/pcsc/wrapper/winscard.c
+++ b/sesman/chansrv/pcsc/wrapper/winscard.c
@@ -1,3 +1,6 @@
+#if defined(HAVE_CONFIG_H)
+#include <config_ac.h>
+#endif
 
 #include <stdio.h>
 #include <stdlib.h>
diff --git a/sesman/chansrv/pcsc/xrdp_pcsc.c b/sesman/chansrv/pcsc/xrdp_pcsc.c
index 3f461fbe..220c97c7 100644
--- a/sesman/chansrv/pcsc/xrdp_pcsc.c
+++ b/sesman/chansrv/pcsc/xrdp_pcsc.c
@@ -1,3 +1,6 @@
+#if defined(HAVE_CONFIG_H)
+#include <config_ac.h>
+#endif
 
 #include <stdio.h>
 #include <stdlib.h>
diff --git a/tools/devel/gtcp_proxy/gtcp-proxy.c b/tools/devel/gtcp_proxy/gtcp-proxy.c
index 48a1b55d..d081a04c 100644
--- a/tools/devel/gtcp_proxy/gtcp-proxy.c
+++ b/tools/devel/gtcp_proxy/gtcp-proxy.c
@@ -16,6 +16,10 @@
  * limitations under the License.
  */
 
+#if defined(HAVE_CONFIG_H)
+#include <config_ac.h>
+#endif
+
 #include <stdio.h>
 #include <gtk/gtk.h>
 #include <pthread.h>
diff --git a/tools/devel/gtcp_proxy/gtcp.c b/tools/devel/gtcp_proxy/gtcp.c
index a0f1660d..6e52babc 100644
--- a/tools/devel/gtcp_proxy/gtcp.c
+++ b/tools/devel/gtcp_proxy/gtcp.c
@@ -16,6 +16,10 @@
  * limitations under the License.
  */
 
+#if defined(HAVE_CONFIG_H)
+#include <config_ac.h>
+#endif
+
 #include "gtcp.h"
 
 /**
diff --git a/tools/devel/gtcp_proxy/hexdump.c b/tools/devel/gtcp_proxy/hexdump.c
index 0475f2f0..5bb0d395 100644
--- a/tools/devel/gtcp_proxy/hexdump.c
+++ b/tools/devel/gtcp_proxy/hexdump.c
@@ -16,6 +16,10 @@
  * limitations under the License.
  */
 
+#if defined(HAVE_CONFIG_H)
+#include <config_ac.h>
+#endif
+
 #include <stdio.h>
 #include <stdint.h>
 #include <string.h>