Re: [Qemu-devel] [PATCH 01/14] trace: Add trace-events file for declaring trace events

[Andreas Färber]

Hello Stefan,

Am 06.09.2010 um 17:13 schrieb Stefan Hajnoczi:

> diff --git a/Makefile b/Makefile
> index f95cc2f..3c5e6a0 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -1,6 +1,6 @@
> # Makefile for QEMU.
>
> -GENERATED_HEADERS = config-host.h
> +GENERATED_HEADERS = config-host.h trace.h
>
> ifneq ($(wildcard config-host.mak),)
> # Put the all: rule here so that config-host.mak can contain  
> dependencies.
> @@ -104,16 +104,24 @@ ui/vnc.o: QEMU_CFLAGS += $(VNC_TLS_CFLAGS)
>
> bt-host.o: QEMU_CFLAGS += $(BLUEZ_CFLAGS)
>
> +trace.h: $(SRC_PATH)/trace-events config-host.mak
> +	$(call quiet-command,sh $(SRC_PATH)/tracetool --$(TRACE_BACKEND) - 
> h < $< > $@,"  GEN   $@")
> +
> +trace.c: $(SRC_PATH)/trace-events config-host.mak
> +	$(call quiet-command,sh $(SRC_PATH)/tracetool --$(TRACE_BACKEND) - 
> c < $< > $@,"  GEN   $@")
> +
> +trace.o: trace.c $(GENERATED_HEADERS)

There's a dependency issue hidden here: The user emulators recurse  
into *-user with just a dependency on trace.h. The build then fails  
because the target Makefile does not know how to build ../trace.o  
since the rule is in this Makefile instead.

I noticed it with ppc-haiku-user but this should be visible with linux- 
user on a clean build, too.

Adding trace.o or $(trace-obj-y) somewhere before subdir-libuser seems  
to help. I'll post a patch later on if no one beats me.

Andreas

> +
> ######################################################################
>
> qemu-img.o: qemu-img-cmds.h
> qemu-img.o qemu-tool.o qemu-nbd.o qemu-io.o: $(GENERATED_HEADERS)
>
> -qemu-img$(EXESUF): qemu-img.o qemu-tool.o qemu-error.o $(block-obj- 
> y) $(qobject-obj-y)
> +qemu-img$(EXESUF): qemu-img.o qemu-tool.o qemu-error.o $(trace-obj- 
> y) $(block-obj-y) $(qobject-obj-y)
>
> -qemu-nbd$(EXESUF): qemu-nbd.o qemu-tool.o qemu-error.o $(block-obj- 
> y) $(qobject-obj-y)
> +qemu-nbd$(EXESUF): qemu-nbd.o qemu-tool.o qemu-error.o $(trace-obj- 
> y) $(block-obj-y) $(qobject-obj-y)
>
> -qemu-io$(EXESUF): qemu-io.o cmd.o qemu-tool.o qemu-error.o $(block- 
> obj-y) $(qobject-obj-y)
> +qemu-io$(EXESUF): qemu-io.o cmd.o qemu-tool.o qemu-error.o $(trace- 
> obj-y) $(block-obj-y) $(qobject-obj-y)
>
> qemu-img-cmds.h: $(SRC_PATH)/qemu-img-cmds.hx
>         $(call quiet-command,sh $(SRC_PATH)/hxtool -h < $< > $@,"  GEN   $@")
> @@ -133,6 +141,7 @@ clean:
>         rm -f *.o *.d *.a $(TOOLS) TAGS cscope.* *.pod *~ */*~
> 	rm -f slirp/*.o slirp/*.d audio/*.o audio/*.d block/*.o block/*.d  
> net/*.o net/*.d fsdev/*.o fsdev/*.d ui/*.o ui/*.d
>         rm -f qemu-img-cmds.h
> +       rm -f trace.c trace.h
>         $(MAKE) -C tests clean
> 	for d in $(ALL_SUBDIRS) libhw32 libhw64 libuser libdis libdis-user;  
> do \
>         if test -d $$d; then $(MAKE) -C $$d $@ || exit 1; fi; \