The rules to build Makefile.mtest are suffering from the "tunnel vision"
problem that is common with recursive makefiles. Makefile.mtest depends
on build.ninja, but Make does not know when build.ninja needs to be
rebuilt before creating Makefile.mtest.
To fix this, separate the ninja invocation into the "regenerate build
files" phase and the QEMU build phase. Sentinel files such as
meson-private/coredata.dat or build.ninja are used to figure out the
phases that haven't run yet; however, because those files' timestamps
are not guaranteed to be touched, the usual makefile stamp-file trick
is used on top.
Thanks for the quick response. Unfortunately, it doesn't seem to work quite right for me.
I think it should be possible to reproduce on unmodified upstream sources like this:
$ cd bin/opt/arm
$ ../../../configure --target-list=arm-softmmu
$ make check-qtest # Feel free to interrupt after verifying that npcm7xx_timer-test is run
$ cd -
$ git revert 19d50149c857e50ccb1ee35dd4277f9d4954877f
Removing tests/qtest/npcm7xx_timer-test.c
[meson-test 3ce2b719aa] Revert "tests/qtest: Add npcm7xx timer test"
2 files changed, 563 deletions(-)
delete mode 100644 tests/qtest/npcm7xx_timer-test.c
$ cd -
$ make check-qtest
After the revert, check-qtest still runs npcm7xx_timer-test. Note that it doesn't fail because the patch I reverted only adds a new test, it doesn't touch the device being tested.
If you run 'make check-qtest' again, npcm7xx_timer-test does not run. Interestingly, it looks like Makefile.mtest gets regenerated here -- I didn't notice that happening in the first run, nor does it happen if I run make check-qtest a third time.
Reported-by: Havard Skinnemoen <hskinnemoen@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
Makefile | 42 +++++++++++++++++++++++++++++++-----------
1 file changed, 31 insertions(+), 11 deletions(-)
diff --git a/Makefile b/Makefile
index 18f026eac3..007ad4d863 100644
--- a/Makefile
+++ b/Makefile
@@ -92,6 +92,8 @@ endif
ifeq ($(NINJA),)
.PHONY: config-host.mak
x := $(shell rm -rf meson-private meson-info meson-logs)
+else
+export NINJA
endif
ifeq ($(wildcard build.ninja),)
.PHONY: config-host.mak
@@ -100,31 +102,46 @@ endif
# 1. ensure config-host.mak is up-to-date
config-host.mak: $(SRC_PATH)/configure $(SRC_PATH)/pc-bios $(SRC_PATH)/VERSION
- @echo $@ is out-of-date, running configure
+ @echo config-host.mak is out-of-date, running configure
@if test -f meson-private/coredata.dat; then \
./config.status --skip-meson; \
else \
- ./config.status; \
+ ./config.status && touch build.ninja.stamp; \
fi
-# 2. ensure generated build files are up-to-date
+# 2. meson.stamp exists if meson has run at least once (so ninja reconfigure
+# works), but otherwise never needs to be updated
+meson-private/coredata.dat: meson.stamp
+meson.stamp: config-host.mak
+ @touch meson.stamp
+
+# 3. ensure generated build files are up-to-date
-ifneq ($(NINJA),)
# A separate rule is needed for Makefile dependencies to avoid -n
-export NINJA
+ifneq ($(MESON),)
+build.ninja: build.ninja.stamp
+build.ninja.stamp: meson.stamp
+ $(NINJA) $(if $V,-v,) reconfigure && touch $@
+endif
+
+ifneq ($(NINJA),)
Makefile.ninja: build.ninja
- $(quiet-@){ echo 'ninja-targets = \'; $(NINJA) -t targets all | sed 's/:.*//; $$!s/$$/ \\/'; } > $@
+ $(quiet-@){ \
+ echo 'ninja-targets = \'; \
+ $(NINJA) -t targets all | sed 's/:.*//; $$!s/$$/ \\/'; \
+ echo 'build-files = \'; \
+ $(NINJA) -t query build.ninja | sed -n '1,/^ input:/d; /^ outputs:/q; s/$$/ \\/p'; \
+ } > $@.tmp && mv $@.tmp $@
-include Makefile.ninja
endif
ifneq ($(MESON),)
-# The dependency on config-host.mak ensures that meson has run
-Makefile.mtest: build.ninja scripts/mtest2make.py config-host.mak
+Makefile.mtest: build.ninja scripts/mtest2make.py
$(MESON) introspect --targets --tests --benchmarks | $(PYTHON) scripts/mtest2make.py > $@
-include Makefile.mtest
endif
-# 3. Rules to bridge to other makefiles
+# 4. Rules to bridge to other makefiles
ifneq ($(NINJA),)
NINJAFLAGS = $(if $V,-v,) \
@@ -135,7 +152,10 @@ ninja-cmd-goals = $(or $(MAKECMDGOALS), all)
ninja-cmd-goals += $(foreach t, $(.tests), $(.test.deps.$t))
makefile-targets := build.ninja ctags TAGS cscope dist clean uninstall
-ninja-targets := $(filter-out $(makefile-targets), $(ninja-targets))
+# "ninja -t targets" also lists all prerequisites. If build system
+# files are marked as PHONY, however, Make will always try to execute
+# "ninja reconfigure" to rebuild build.ninja.
+ninja-targets := $(filter-out $(build-files) $(makefile-targets), $(ninja-targets))
.PHONY: $(ninja-targets) run-ninja
$(ninja-targets): run-ninja
@@ -214,7 +234,7 @@ distclean: clean
rm -f qemu-plugins-ld.symbols qemu-plugins-ld64.symbols
rm -f *-config-target.h *-config-devices.mak *-config-devices.h
rm -rf meson-private meson-logs meson-info compile_commands.json
- rm -f Makefile.ninja Makefile.mtest
+ rm -f Makefile.ninja Makefile.mtest build.ninja.stamp meson.stamp
rm -f config.log
rm -f linux-headers/asm
rm -Rf .sdk
--
2.26.2