diff --git a/lib/isc/include/isc/hmac.h b/lib/isc/include/isc/hmac.h
index 20bcde3d0a..aca85b4933 100644
--- a/lib/isc/include/isc/hmac.h
+++ b/lib/isc/include/isc/hmac.h
@@ -16,8 +16,6 @@
 
 #pragma once
 
-#include <config.h>
-
 #include <isc/lang.h>
 #include <isc/md.h>
 #include <isc/platform.h>
diff --git a/lib/isc/include/isc/md.h b/lib/isc/include/isc/md.h
index a3f16ebd5b..1645d4162e 100644
--- a/lib/isc/include/isc/md.h
+++ b/lib/isc/include/isc/md.h
@@ -16,8 +16,6 @@
 
 #pragma once
 
-#include <config.h>
-
 #include <isc/lang.h>
 #include <isc/platform.h>
 #include <isc/types.h>
diff --git a/lib/isc/include/isc/strerr.h b/lib/isc/include/isc/strerr.h
index e3e0304dab..1d16819769 100644
--- a/lib/isc/include/isc/strerr.h
+++ b/lib/isc/include/isc/strerr.h
@@ -13,8 +13,6 @@
 
 /*! \file isc/strerr.h */
 
-#include <config.h>
-
 #include <string.h>
 
 #if defined(strerror_r)