We make a few sub-directories recursively, in particular
$(TARGET_DIRS).

For goal "all", we do it the nice way: "all" has a prerequisite
subdir-T for each T in $(TARGET_DIRS), and T's recipe runs make
recursively.  Behaves nicely with -j and -k.

For other goals such as "clean" and "install", the recipe runs make
recursively in a for loop.  Ignores -j and -k.

The next commit will fix that for "clean" and "install".  This commit
prepares the ground by renaming the targets we use for "all" to
include the goal for the sub-make.  This will permit reusing them for
goals other than "all".

Targets subdir-T for T in $(TARGET_DIRS) run "make all" in T.  Rename
to T/all, and declare phony.

Targets romsubdir-R for R in $(ROMS) run "make" in pc-bios/R.  Default
goal is "all" for all R.  Rename to pc-bios/R/all, and declare phony.

The remainder are renamed just for consistency.

Target subdir-dtc runs "make libbft/libfdt.a" in dtc.  Rename to
dtc/all, and declare phony.

Target subdir-capstone runs make $(BUILD_DIR)/capstone/$(LIBCAPSTONE)
in $(SRC_PATH)/capstone.  Rename to capstone/all, and declare phony.

Target subdir-slirp runs "make" in $(SRC_PATH)/slirp.  Default goal is
all, which builds $(BUILD_DIR)/libslirp.a.  Rename to slirp/all, and
declare phony.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 Makefile               | 30 ++++++++++++++++++------------
 configure              |  6 +++---
 tests/Makefile.include |  5 +++--
 3 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/Makefile b/Makefile
index 80c9c6416f..42930b7749 100644
--- a/Makefile
+++ b/Makefile
@@ -437,8 +437,8 @@ config-host.h-timestamp: config-host.mak
 qemu-options.def: $(SRC_PATH)/qemu-options.hx $(SRC_PATH)/scripts/hxtool
 	$(call quiet-command,sh $(SRC_PATH)/scripts/hxtool -h < $< > $@,"GEN","$@")
 
-SUBDIR_RULES=$(patsubst %,subdir-%, $(TARGET_DIRS))
-SOFTMMU_SUBDIR_RULES=$(filter %-softmmu,$(SUBDIR_RULES))
+SUBDIR_RULES=$(addsuffix /all, $(TARGET_DIRS))
+SOFTMMU_SUBDIR_RULES=$(filter %-softmmu/all,$(SUBDIR_RULES))
 
 $(SOFTMMU_SUBDIR_RULES): $(authz-obj-y)
 $(SOFTMMU_SUBDIR_RULES): $(block-obj-y)
@@ -448,14 +448,16 @@ $(SOFTMMU_SUBDIR_RULES): $(io-obj-y)
 $(SOFTMMU_SUBDIR_RULES): config-all-devices.mak
 $(SOFTMMU_SUBDIR_RULES): $(edk2-decompressed)
 
-subdir-%:
-	$(call quiet-command,$(MAKE) $(SUBDIR_MAKEFLAGS) -C $* V="$(V)" TARGET_DIR="$*/" all,)
+.PHONY: $(SUBDIR_RULES)
+$(SUBDIR_RULES):
+	$(call quiet-command,$(MAKE) $(SUBDIR_MAKEFLAGS) -C $(dir $@) V="$(V)" TARGET_DIR="$(dir $@)" all,)
 
 DTC_MAKE_ARGS=-I$(SRC_PATH)/dtc VPATH=$(SRC_PATH)/dtc -C dtc V="$(V)" LIBFDT_srcdir=$(SRC_PATH)/dtc/libfdt
 DTC_CFLAGS=$(CFLAGS) $(QEMU_CFLAGS)
 DTC_CPPFLAGS=-I$(BUILD_DIR)/dtc -I$(SRC_PATH)/dtc -I$(SRC_PATH)/dtc/libfdt
 
-subdir-dtc: .git-submodule-status dtc/libfdt dtc/tests
+.PHONY: dtc/all
+dtc/all: .git-submodule-status dtc/libfdt dtc/tests
 	$(call quiet-command,$(MAKE) $(DTC_MAKE_ARGS) CPPFLAGS="$(DTC_CPPFLAGS)" CFLAGS="$(DTC_CFLAGS)" LDFLAGS="$(LDFLAGS)" ARFLAGS="$(ARFLAGS)" CC="$(CC)" AR="$(AR)" LD="$(LD)" $(SUBDIR_MAKEFLAGS) libfdt/libfdt.a,)
 
 dtc/%: .git-submodule-status
@@ -473,21 +475,25 @@ CAP_CFLAGS += -DCAPSTONE_HAS_ARM64
 CAP_CFLAGS += -DCAPSTONE_HAS_POWERPC
 CAP_CFLAGS += -DCAPSTONE_HAS_X86
 
-subdir-capstone: .git-submodule-status
+.PHONY: capstone/all
+capstone/all: .git-submodule-status
 	$(call quiet-command,$(MAKE) -C $(SRC_PATH)/capstone CAPSTONE_SHARED=no BUILDDIR="$(BUILD_DIR)/capstone" CC="$(CC)" AR="$(AR)" LD="$(LD)" RANLIB="$(RANLIB)" CFLAGS="$(CAP_CFLAGS)" $(SUBDIR_MAKEFLAGS) $(BUILD_DIR)/capstone/$(LIBCAPSTONE))
 
-subdir-slirp: .git-submodule-status
+.PHONY: slirp/all
+slirp/all: .git-submodule-status
 	$(call quiet-command,$(MAKE) -C $(SRC_PATH)/slirp BUILD_DIR="$(BUILD_DIR)/slirp" CC="$(CC)" AR="$(AR)" LD="$(LD)" RANLIB="$(RANLIB)" CFLAGS="$(QEMU_CFLAGS) $(CFLAGS)" LDFLAGS="$(LDFLAGS)")
 
 $(SUBDIR_RULES): libqemuutil.a $(common-obj-y) \
 	$(qom-obj-y) $(crypto-user-obj-$(CONFIG_USER_ONLY))
 
-ROMSUBDIR_RULES=$(patsubst %,romsubdir-%, $(ROMS))
+ROM_DIRS = $(addprefix pc-bios/, $(ROMS))
+ROMSUBDIR_RULES=$(addsuffix /all, $(ROM_DIRS))
 # Only keep -O and -g cflags
-romsubdir-%:
-	$(call quiet-command,$(MAKE) $(SUBDIR_MAKEFLAGS) -C pc-bios/$* V="$(V)" TARGET_DIR="$*/" CFLAGS="$(filter -O% -g%,$(CFLAGS))",)
+.PHONY: $(ROMSUBDIR_RULES)
+$(ROMSUBDIR_RULES):
+	$(call quiet-command,$(MAKE) $(SUBDIR_MAKEFLAGS) -C $(dir $@) V="$(V)" TARGET_DIR="$(dir $@)" CFLAGS="$(filter -O% -g%,$(CFLAGS))",)
 
-ALL_SUBDIRS=$(TARGET_DIRS) $(patsubst %,pc-bios/%, $(ROMS))
+ALL_SUBDIRS=$(TARGET_DIRS) $(ROM_DIRS)
 
 recurse-all: $(SUBDIR_RULES) $(ROMSUBDIR_RULES)
 
@@ -1098,7 +1104,7 @@ endif
 	@$(if $(TARGET_DIRS), \
 		echo 'Architecture specific targets:'; \
 		$(foreach t, $(TARGET_DIRS), \
-		printf "  %-30s - Build for %s\\n" $(patsubst %,subdir-%,$(t)) $(t);) \
+		printf "  %-30s - Build for %s\\n" $(t)/all $(t);) \
 		echo '')
 	@echo  'Cleaning targets:'
 	@echo  '  clean           - Remove most generated files but keep the config'
diff --git a/configure b/configure
index 528b9ff705..effd943a05 100755
--- a/configure
+++ b/configure
@@ -6597,7 +6597,7 @@ if test "$slirp" != "no"; then
   echo "SLIRP_LIBS=$slirp_libs" >> $config_host_mak
 fi
 if [ "$slirp" = "git" -o "$slirp" = "internal" ]; then
-    echo "config-host.h: subdir-slirp" >> $config_host_mak
+    echo "config-host.h: slirp/all" >> $config_host_mak
 fi
 if test "$vde" = "yes" ; then
   echo "CONFIG_VDE=y" >> $config_host_mak
@@ -7865,10 +7865,10 @@ if test -n "$enabled_cross_compilers"; then
 fi
 
 if [ "$fdt" = "git" ]; then
-  echo "config-host.h: subdir-dtc" >> $config_host_mak
+  echo "config-host.h: dtc/all" >> $config_host_mak
 fi
 if [ "$capstone" = "git" -o "$capstone" = "internal" ]; then
-  echo "config-host.h: subdir-capstone" >> $config_host_mak
+  echo "config-host.h: capstone/all" >> $config_host_mak
 fi
 if test -n "$LIBCAPSTONE"; then
   echo "LIBCAPSTONE=$LIBCAPSTONE" >> $config_host_mak
diff --git a/tests/Makefile.include b/tests/Makefile.include
index 1865f6b322..1a3f17faa9 100644
--- a/tests/Makefile.include
+++ b/tests/Makefile.include
@@ -1,3 +1,4 @@
+# -*- Mode: makefile -*-
 
 .PHONY: check-help
 check-help:
@@ -880,7 +881,7 @@ define do_test_tap
 endef
 
 .PHONY: $(patsubst %, check-qtest-%, $(QTEST_TARGETS))
-$(patsubst %, check-qtest-%, $(QTEST_TARGETS)): check-qtest-%: subdir-%-softmmu $(check-qtest-y)
+$(patsubst %, check-qtest-%, $(QTEST_TARGETS)): check-qtest-%: %-softmmu/all $(check-qtest-y)
 	$(call do_test_human,$(check-qtest-$*-y) $(check-qtest-generic-y), \
 	  QTEST_QEMU_BINARY=$*-softmmu/qemu-system-$* \
 	  QTEST_QEMU_IMG=qemu-img$(EXESUF))
@@ -893,7 +894,7 @@ check-speed: $(check-speed-y)
 
 # gtester tests with TAP output
 
-$(patsubst %, check-report-qtest-%.tap, $(QTEST_TARGETS)): check-report-qtest-%.tap: subdir-%-softmmu $(check-qtest-y)
+$(patsubst %, check-report-qtest-%.tap, $(QTEST_TARGETS)): check-report-qtest-%.tap: %-softmmu/all $(check-qtest-y)
 	$(call do_test_tap, $(check-qtest-$*-y) $(check-qtest-generic-y), \
 	  QTEST_QEMU_BINARY=$*-softmmu/qemu-system-$* \
 	  QTEST_QEMU_IMG=qemu-img$(EXESUF))
-- 
2.17.2

Peter pointed out that this makes an incremental build without -k fail
once.  By "once", I mean it works fine when you retry.  Squashing in the
appended patch to avoid this inconvenience.


diff --git a/Makefile b/Makefile
index e68982bd99..34bbcfc590 100644
--- a/Makefile
+++ b/Makefile
@@ -500,6 +500,12 @@ capstone/all: .git-submodule-status
 slirp/all: .git-submodule-status
 	$(call quiet-command,$(MAKE) -C $(SRC_PATH)/slirp BUILD_DIR="$(BUILD_DIR)/slirp" CC="$(CC)" AR="$(AR)" LD="$(LD)" RANLIB="$(RANLIB)" CFLAGS="$(QEMU_CFLAGS) $(CFLAGS)" LDFLAGS="$(LDFLAGS)")
 
+# Compatibility gunk to keep make working across the rename of targets
+# for recursion, to be removed some time after 4.1.
+subdir-dtc: dtc/all
+subdir-capstone: capstone/all
+subdir-slirp: slirp/all
+
 $(SUBDIR_RULES): libqemuutil.a $(common-obj-y) \
 	$(qom-obj-y) $(crypto-user-obj-$(CONFIG_USER_ONLY))
 

On 7/3/19 1:24 PM, Markus Armbruster wrote:
> Peter pointed out that this makes an incremental build without -k fail
> once.  By "once", I mean it works fine when you retry.  Squashing in the
> appended patch to avoid this inconvenience.
> 
> 
> diff --git a/Makefile b/Makefile
> index e68982bd99..34bbcfc590 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -500,6 +500,12 @@ capstone/all: .git-submodule-status
>  slirp/all: .git-submodule-status
>  	$(call quiet-command,$(MAKE) -C $(SRC_PATH)/slirp BUILD_DIR="$(BUILD_DIR)/slirp" CC="$(CC)" AR="$(AR)" LD="$(LD)" RANLIB="$(RANLIB)" CFLAGS="$(QEMU_CFLAGS) $(CFLAGS)" LDFLAGS="$(LDFLAGS)")
>  
> +# Compatibility gunk to keep make working across the rename of targets
> +# for recursion, to be removed some time after 4.1.
> +subdir-dtc: dtc/all
> +subdir-capstone: capstone/all
> +subdir-slirp: slirp/all
> +
>  $(SUBDIR_RULES): libqemuutil.a $(common-obj-y) \
>  	$(qom-obj-y) $(crypto-user-obj-$(CONFIG_USER_ONLY))
>  

Both tags stand:
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
(on top of previous patch)