Fix "make install-headers" again

It must not recursively descent into source directories, and must not
depend on a cross-compiler already being available

Author: th-otto

Makefile

@@ -133,7 +133,7 @@ install-lib: all install-lib-recursive
 
 install-include: all install-include-recursive
 
-install-headers: install-include-recursive
+install-headers: install-headers-recursive
 
 install-man: all install-man-recursive
 
@@ -249,6 +249,18 @@ uninstall-include-recursive uninstall-man-recursive:
 	   || case "$$amf" in *=*) exit 1;; *k*) fail=yes;; *) exit 1;; esac; \
 	done && test -z "$$fail"
 
+install-headers-recursive:
+	if test "${CROSS}" = yes -a "$(DESTDIR)${prefix}" = "/usr"; then \
+	   echo "attempting to install on host; aborting" >&2; \
+           exit 1; \
+	fi; \
+	list='include'; \
+	for subdir in $$list; do \
+	  target=`echo $@ | sed s/-recursive//`; \
+	  echo "Making $$target in $$subdir"; \
+	  $(MAKE) -C $$subdir $$target || exit 1; \
+	done
+
 dist-recursive bindist-recursive:
 	@set fnord $(MAKEFLAGS); amf=$$2; \
 	list='$(DIST_SUBDIRS)'; for subdir in $$list; do \

include/Makefile

@@ -78,7 +78,7 @@ syscall-list.h: $(csrcdir)/syscalls.list $(csrcdir)/gensys
 
 includefiles = $(filter %.h, $(MISCFILES)) stab.def syscall-list.h
 
-install-include: remove-stale
+install-include install-headers: remove-stale
 	$(mkinstalldirs) $(DESTDIR)$(includedir)
 	@list='$(includefiles)'; for p in $$list; do \
   	  if test -f $$p; then \

include/arpa/Makefile

@@ -30,7 +30,7 @@ include $(top_srcdir)/rules
 
 includefiles = $(filter %.h, $(MISCFILES))
 
-install-include: 
+install-include install-headers:
 	$(mkinstalldirs) $(DESTDIR)$(includedir)/$(subdir)
 	@list='$(includefiles)'; for p in $$list; do \
   	  if test -f $$p; then \

include/bits/Makefile

@@ -32,7 +32,7 @@ include $(top_srcdir)/rules
 
 includefiles = $(filter %.h, $(MISCFILES))
 
-install-include: 
+install-include install-headers:
 	$(mkinstalldirs) $(DESTDIR)$(includedir)/$(subdir)
 	@list='$(includefiles)'; for p in $$list; do \
   	  if test -f $$p; then \

include/bits/types/Makefile

@@ -30,7 +30,7 @@ include $(top_srcdir)/rules
 
 includefiles = $(filter %.h, $(MISCFILES))
 
-install-include: 
+install-include install-headers:
 	$(mkinstalldirs) $(DESTDIR)$(includedir)/$(subdir)
 	@list='$(includefiles)'; for p in $$list; do \
   	  if test -f $$p; then \

include/mint/Makefile

@@ -32,7 +32,7 @@ include $(top_srcdir)/rules
 
 includefiles = $(filter %.h, $(MISCFILES))
 
-install-include: 
+install-include install-headers:
 	$(mkinstalldirs) $(DESTDIR)$(includedir)/$(subdir)
 	@list='$(includefiles)'; for p in $$list; do \
   	  if test -f $$p; then \

include/mint/arch/Makefile

@@ -30,7 +30,7 @@ include $(top_srcdir)/rules
 
 includefiles = $(filter %.h, $(MISCFILES))
 
-install-include: 
+install-include install-headers:
 	$(mkinstalldirs) $(DESTDIR)$(includedir)/$(subdir)
 	@list='$(includefiles)'; for p in $$list; do \
   	  if test -f $$p; then \

include/net/Makefile

@@ -30,7 +30,7 @@ include $(top_srcdir)/rules
 
 includefiles = $(filter %.h, $(MISCFILES))
 
-install-include: 
+install-include install-headers:
 	$(mkinstalldirs) $(DESTDIR)$(includedir)/$(subdir)
 	@list='$(includefiles)'; for p in $$list; do \
   	  if test -f $$p; then \

include/netinet/Makefile

@@ -30,7 +30,7 @@ include $(top_srcdir)/rules
 
 includefiles = $(filter %.h, $(MISCFILES))
 
-install-include: 
+install-include install-headers:
 	$(mkinstalldirs) $(DESTDIR)$(includedir)/$(subdir)
 	@list='$(includefiles)'; for p in $$list; do \
   	  if test -f $$p; then \

include/nfs/Makefile

@@ -31,7 +31,7 @@ include $(top_srcdir)/rules
 includefiles = $(filter %.h, $(MISCFILES))
 includefiles += $(filter %.x, $(MISCFILES))
 
-install-include: 
+install-include install-headers:
 	$(mkinstalldirs) $(DESTDIR)$(includedir)/$(subdir)
 	@list='$(includefiles)'; for p in $$list; do \
   	  if test -f $$p; then \