Avoid makefile error and change ucontext.h to sys/ucontext.h.

Rakefile

@@ -101,12 +101,12 @@ namespace :driver do
     %x(rm -rf #{target} && mkdir -p #{target}/driver && mkdir -p #{target}/kernel)
 
     %x(cp -r #{source}/{AUTHORS,COPYRIGHT,LICENSE} #{target})
-    %x(cp -r #{source}/{depend.sed,ver,Makefile.include,Makefile.platform} #{target})
+    %x(cp -r #{source}/{depend.sed,ver,Makefile.include,Makefile.platform,Makefile.pseudolib} #{target})
     %x(cp -r #{source}/driver/c #{target}/driver/c)
     %x(cp -r #{source}/kernel/common #{target}/kernel/common)
 
     u_h = File.read("#{target}/kernel/common/u/u.h")
-    u_h.gsub!("#include <ucontext.h>", "")
+    u_h.gsub!("#include <ucontext.h>", "#include <sys/ucontext.h>")
     File.open("#{target}/kernel/common/u/u.h", "w") do |f|
       f.write u_h
     end

vendor/sedna/Makefile.pseudolib

@@ -0,0 +1,74 @@
+#
+# Common part for all pseudo libs
+#
+
+#No target is removed because it is considered intermediate
+.SECONDARY:
+
+FOLDER = $(shell basename `pwd`)
+SUBDIROBJS= $(foreach dir,$(SUBDIRS),$(dir)/$(dir)$(LIST_EXT))
+
+all: $(FOLDER)$(LIST_EXT)
+	@echo ===================================================================
+	@echo $(FOLDER) DONE
+	@echo ===================================================================
+
+ifneq ($(findstring clean, $(MAKECMDGOALS)), clean)
+ifndef NO_DEP
+
+ifdef GENERATED
+include generated
+endif
+
+include $(OBJS:$(OBJ_EXT)=.d)
+
+ifdef GENERATED
+$(OBJS:$(OBJ_EXT)=.d): generated
+endif
+
+else
+
+ifdef GENERATED
+include generated
+endif
+
+ifdef GENERATED
+$(OBJS): generated
+endif
+
+endif
+endif
+
+
+################################################################################
+# $(FOLDER)                                                                    #
+################################################################################
+$(FOLDER)$(LIST_EXT): $(OBJS) $(SUBDIROBJS)
+	echo $(foreach obj,$(foreach dirobj,$(SUBDIROBJS),$(shell cat $(dirobj))) $(OBJS),$(FOLDER)/$(obj)) >$@
+
+
+$(SUBDIROBJS): $(SUBDIRS:%=%-recursive) ;
+
+.PHONY: $(SUBDIRS:%=%-recursive)
+$(SUBDIRS:%=%-recursive):
+	$(MAKE) -C $(subst -recursive,,$@)
+
+
+ifdef GENERATED
+$(GENERATED): generated
+endif
+
+
+################################################################################
+# Clean                                                                        #
+################################################################################
+.PHONY: clean Makefile $(CUSTOM_CLEAN)
+
+Makefile: ;
+
+clean: generic_clean $(CUSTOM_CLEAN)
+	-rm -f $(FOLDER)$(LIST_EXT)
+ifdef SUBDIRS
+	for dir in $(SUBDIRS); do $(MAKE) -C $$dir $@ || exit; done
+endif
+

vendor/sedna/kernel/common/u/u.h

@@ -199,7 +199,7 @@
 #include <signal.h>
 
 #ifndef __cygwin__
-
+#include <sys/ucontext.h>
 #endif
 
 #include <setjmp.h>