diff --git a/Makefile.inc1 b/Makefile.inc1
index 4edb3e7e8df3..6b6a17041543 100644
--- a/Makefile.inc1
+++ b/Makefile.inc1
@@ -625,6 +625,7 @@ legacy:
 	@${ECHODIR} "===> ${_tool}"; \
 	    cd ${.CURDIR}/${_tool}; \
 	    ${MAKE} DIRPRFX=${_tool}/ obj; \
+	    ${MAKE} DIRPRFX=${_tool}/ DESTDIR=${MAKEOBJDIRPREFIX}/legacy includes; \
 	    ${MAKE} DIRPRFX=${_tool}/ depend; \
 	    ${MAKE} DIRPRFX=${_tool}/ all; \
 	    ${MAKE} DIRPRFX=${_tool}/ DESTDIR=${MAKEOBJDIRPREFIX}/legacy install
diff --git a/tools/build/Makefile b/tools/build/Makefile
index 2dc1a27eaf8b..4bf29342970c 100644
--- a/tools/build/Makefile
+++ b/tools/build/Makefile
@@ -31,9 +31,9 @@ INCS+=		stdbool.h
 INCS+=		langinfo.h
 .endif
 
-# gnu/usr.bin/binutils/libiberty needs basename(3).
-.if ( ${BOOTSTRAPPING} < 440000 || \
-    ( ${BOOTSTRAPPING} >= 500000 && ${BOOTSTRAPPING} < 500022 ))
+# Some tools need basename(3).
+.if !exists(/usr/include/libgen.h)
+INCS+=		libgen.h
 .PATH: ${.CURDIR}/../../lib/libc/gen
 SRCS+=		basename.c
 .endif