https://bugs.gentoo.org/888829

--- a/apps/Makefile
+++ b/apps/Makefile
@@ -41,9 +41,7 @@
 
 include $(SRCDIR)/../Make.defaults
 
-LINUX_HEADERS	= /usr/src/sys/build
 APPSDIR		= $(LIBDIR)/gnuefi/apps
-CPPFLAGS	+= -D__KERNEL__ -I$(LINUX_HEADERS)/include
 
 ifneq ($(HAVE_EFI_OBJCOPY),)
 ifeq ($(SYSTEM_HAS_EFI_OBJCOPY),0)