Place compiled objects and dependencies in build/

- generate dependencies during compile rather than explicitly

2 files changed, 34 insertions, 43 deletions

diff --git a/.gitignore b/.gitignore
index 19429b0..ff952c7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,13 +1,10 @@
 lib/musl*
-build*
-*.d
-*.o
+build
 *.a
 *.elf
 *.iso
 isodir
 src/conf.h
 .config.old
-test_*
 doc
 include/
diff --git a/rules.mk b/rules.mk
index 98aa829..8adbdbe 100644
--- a/rules.mk
+++ b/rules.mk
@@ -2,13 +2,13 @@
 # arg 1:  target.SRCS
 # arg 2:  object suffix prefix
 # returns: target.OBJS
-objects = $(foreach f,$($1),$(addsuffix $2.o,$(basename $f)))
+objects = $(foreach f,$($1),$(addprefix build/,$(addsuffix $2.o,$(basename $f))))
 
 # generate depends from .S .c .cpp sources
 # arg 1:  target.SRCS
 # arg 2:  dependency suffix prefix
 # returns: target.DEPS
-depends = $(foreach f,$(filter %.S %.c %.cpp,$($1)),$(addsuffix $2.d,$(basename $f)))
+depends = $(foreach f,$(filter %.S %.c %.cpp,$($1)),$(addprefix build/,$(addsuffix $2.d,$(basename $f))))
 
 # default target
 .DEFAULT_GOAL := all
@@ -16,19 +16,19 @@ depends = $(foreach f,$(filter %.S %.c %.cpp,$($1)),$(addsuffix $2.d,$(basename
 
 # TARGETBIN: binaries using the target architecture
 $(foreach T,${TARGETBIN},\
-	$(eval  $T.OBJS += $(call objects,$T.SRCS,_${ARCH})   ) \
-	$(eval  $T.DEPS += $(call depends,$T.SRCS,_${ARCH})   ) \
-	$(eval  include $($T.DEPS)                            ) \
-	$(eval  $T.elf: ${$T.OBJS}                            ) \
+	$(eval  $T.OBJS += $(call objects,$T.SRCS,_${ARCH})  ) \
+	$(eval  $T.DEPS += $(call depends,$T.SRCS,_${ARCH})  ) \
+	$(eval  -include $($T.DEPS)                          ) \
+	$(eval  $T.elf: ${$T.OBJS}                           ) \
 	$(eval  DEFAULT_TARGETS += $T.elf) \
 )
 
 # TARGETLIB: static libraries using the target architecture
 $(foreach T,${TARGETLIB},\
-	$(eval  $T.OBJS += $(call objects,$T.SRCS,_${ARCH})   ) \
-	$(eval  $T.DEPS += $(call depends,$T.SRCS,_${ARCH})   ) \
-	$(eval  include $($T.DEPS)                            ) \
-	$(eval  $T.a: ${$T.OBJS}                              ) \
+	$(eval  $T.OBJS += $(call objects,$T.SRCS,_${ARCH})  ) \
+	$(eval  $T.DEPS += $(call depends,$T.SRCS,_${ARCH})  ) \
+	$(eval  -include $($T.DEPS)                          ) \
+	$(eval  $T.a: ${$T.OBJS}                             ) \
 	$(eval  DEFAULT_TARGETS += $T.a) \
 )
 
@@ -36,7 +36,7 @@ $(foreach T,${TARGETLIB},\
 $(foreach T,${HOSTTARGETBIN},\
 	$(eval  $T.OBJS += $(call objects,$T.SRCS,)  ) \
 	$(eval  $T.DEPS += $(call depends,$T.SRCS,)  ) \
-	$(eval  include $($T.DEPS)                   ) \
+	$(eval  -include $($T.DEPS)                  ) \
 	$(eval  $T: ${$T.OBJS}; @echo '  HOST LD    $T'; ${HOST_CXX} ${HOST_LDFLAGS} -o $T ${$T.OBJS}   ) \
 	$(eval  DEFAULT_TARGETS += $T) \
 )
@@ -65,51 +65,45 @@ ${ARCH}_CFLAGS   += -I../lib/libk \
 		    -Werror=implicit-function-declaration
 ${ARCH}_CXXFLAGS += -I../lib/libk -Drestrict=__restrict__
 
-# Target depndency rules
-%_${ARCH}.d: %.S
-	@${${ARCH}_CC} ${${ARCH}_CFLAGS} -M -MT $(<:.S=_${ARCH}.o) $< -MF $@
-
-%_${ARCH}.d: %.c
-	@${${ARCH}_CC} ${${ARCH}_CFLAGS} -M -MT $(<:.c=_${ARCH}.o) $< -MF $@
-
-# Host dependency rules
-%.d: %.c
-	@${HOST_CC} ${HOST_CFLAGS} -M -MT $(<:.c=.o) $< -MF $@
-
-%.d: %.cc
-	@${HOST_CXX} ${HOST_CXXFLAGS} -M -MT $(<:.cc=) $< -MF $@
-
 # Target suffix rules
+# -MD         output makefile dependency rule
+# -MT target  change the target of the rule
+# -MF file    write the dependencies to file
 %.a:
-	@echo '  AR   $@'
+	@echo '       AR    $@'
 	@${${ARCH}_AR} ${${ARCH}_ARFLAGS} $@ $(filter %.o,$^)
 
-%_${ARCH}.o: %.s
-	@echo '  AS   $<'
+build/%_${ARCH}.o: %.s
+	@echo '       AS    $<'
+	@mkdir -p $(dir $@)
 	@${${ARCH}_AS} ${${ARCH}_ASFLAGS} -c -o $@ $<
 
-%_${ARCH}.o: %.S
-	@echo '  CC   $<'
-	@${${ARCH}_CC} ${${ARCH}_CFLAGS} -c -o $@ $<
+build/%_${ARCH}.o: %.S
+	@echo '       CC    $<'
+	@mkdir -p $(dir $@)
+	@${${ARCH}_CC} ${${ARCH}_CFLAGS} -MD -MT $@ -MF $(@:.o=.d) -c -o $@ $<
 
-%_${ARCH}.o: %.c
-	@echo '  CC   $<'
-	@${${ARCH}_CC} ${${ARCH}_CFLAGS} -c -o $@ $<
+build/%_${ARCH}.o: %.c
+	@echo '       CC    $<'
+	@mkdir -p $(dir $@)
+	@${${ARCH}_CC} ${${ARCH}_CFLAGS} -MD -MT $@ -MF $(@:.o=.d) -c -o $@ $<
 
 %.elf:
-	@echo '  LD   $@'
+	@echo '       LD    $@'
 	@${${ARCH}_LD} ${${ARCH}_LDFLAGS} -o $@ $^
 	@echo -n '  B2b  '
 	@b2sum $@ | cut -d' ' -f1
 
 # Host suffix rules
-%.o: %.c
+build/%.o: %.c
 	@echo '  HOST CC    $<'
-	@${HOST_CC} ${HOST_CFLAGS} -c -o $@ $<
+	@mkdir -p $(dir $@)
+	@${HOST_CC} ${HOST_CFLAGS} -MD -MT $@ -MF $(@:.o=.d) -c -o $@ $<
 
-%.o: %.cc
+build/%.o: %.cc
 	@echo '  HOST CXX   $<'
-	@${HOST_CXX} ${HOST_CXXFLAGS} -c -o $@ $<
+	@mkdir -p $(dir $@)
+	@${HOST_CXX} ${HOST_CXXFLAGS} -MD -MT $@ -MF $(@:.o=.d) -c -o $@ $<
 
 .PHONY: test test.quiet valgrind valgrind.quiet clean.base FORCE
 test: ${TESTS}