diff --git a/include/acpi/platform/acenv.h b/include/acpi/platform/acenv.h
index f405113..ee5c0b9 100644
--- a/include/acpi/platform/acenv.h
+++ b/include/acpi/platform/acenv.h
@@ -149,7 +149,6 @@
 /* Common for all ACPICA applications */
 
 #ifdef ACPI_APPLICATION
-#define ACPI_USE_SYSTEM_CLIBRARY
 #define ACPI_USE_LOCAL_CACHE
 #endif
 
@@ -326,7 +325,8 @@
  * ACPI_USE_SYSTEM_CLIBRARY - Define this if linking to an actual C library.
  *      Otherwise, local versions of string/memory functions will be used.
  * ACPI_USE_STANDARD_HEADERS - Define this if linking to a C library and
- *      the standard header files may be used.
+ *      the standard header files may be used. Defining this implies that
+ *      ACPI_USE_SYSTEM_CLIBRARY has been defined.
  *
  * The ACPICA subsystem only uses low level C library functions that do not
  * call operating system services and may therefore be inlined in the code.
@@ -334,7 +334,6 @@
  * It may be necessary to tailor these include files to the target
  * generation environment.
  */
-#ifdef ACPI_USE_SYSTEM_CLIBRARY
 
 /* Use the standard C library headers. We want to keep these to a minimum. */
 
@@ -348,8 +347,6 @@
 
 #endif				/* ACPI_USE_STANDARD_HEADERS */
 
-#endif				/* ACPI_USE_SYSTEM_CLIBRARY */
-
 #ifndef ACPI_FILE
 #ifdef ACPI_APPLICATION
 #include <stdio.h>
diff --git a/include/acpi/platform/aclinux.h b/include/acpi/platform/aclinux.h
index 447c33f..1380ec7 100644
--- a/include/acpi/platform/aclinux.h
+++ b/include/acpi/platform/aclinux.h
@@ -180,10 +180,11 @@
 
 #else				/* !__KERNEL__ */
 
-#include <string.h>
-#include <stdlib.h>
-#include <ctype.h>
+#define ACPI_USE_STANDARD_HEADERS
+
+#ifdef ACPI_USE_STANDARD_HEADERS
 #include <unistd.h>
+#endif
 
 /* Define/disable kernel-specific declarators */