Makefile: Fix build verbosity for V=0

[StefanJum]

When setting V=0, we expect the verbosity level to be reduced, and
only the build output to be printed, not the build commands.
Do that by adding the -s option to MAKEFLAGS in case V is set to 0.

Signed-off-by: Stefan Jumarea stefanjumarea02@gmail.com
GitHub-Fixes: #676

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[kubanrob]

Hi @StefanJum!

Looking at the surrounding code, it seems the underlying problem is that if Q := @ only ever set if V was not set in the command line.

I suspect the code would be to understand / fixed if the following things were separated:

• finding out what verbosity level we want (ifeq ("$(origin V)", "command line") ... else ... endif)
• set the MAKEFLAGS / Q / KBUILD_VERBOSE according to the verbosity

Maybe this is a good chance to clean that up :)

Your solution works for me. However, if I'm not missing something, it seems a new solution to the problem Q is suppose to solve.

[mariasfiraiala]

Hi @kubanrob, I don't really get your point. I've taken a look regarding the usage of Q and it doesn't look that related to what @StefanJum added.

Maybe I'm missing something though. Do correct me if I'm wrong. The changes work, so I'll add my tag after your request gets sorted out.

[razvanvirtan]

Thanks, @StefanJum!
All good on my side.

Reviewed-by: Razvan Virtan virtanrazvan@gmail.com

[kubanrob]

Hello together (@mariasfiraiala), sorry for the late reply!

$Q is used as in the build command, setting it to @ makes the command not be printed by make:

• https://www.gnu.org/software/make/manual/html_node/Echoing.html

• unikraft/support/build/Makefile.rules

  Line 382 in c2bb6c3

  $Q $(UK_FIXDEP) $(call tmp_depfile,$3) $3 '$(SHELL) $(addsuffix .cmd,$(3))' \

So basically Q := @ mechanism aims to do the same as adding -s to the make flags. If you would set Q := @ for the condition were V=0 is set on the command line, the verbosity does not increase.

# To put more focus on warnings, be less verbose as default
# Use 'make V=1' to see the full commands
ifeq ("$(origin V)", "command line")
  BUILD_VERBOSE = $(V) 
else
  BUILD_VERBOSE = 0
endif

ifneq ($(BUILD_VERBOSE),0)
  KBUILD_VERBOSE := 1
  Q :=
else
  # Set KBUILD_VERBOSE and Q to quiet mode
  KBUILD_VERBOSE := 0
  Q := @
endif

So I do not see why -s needs to be added to the $MAKEFLAGS if this bug is fixed. Or if we add the -s, why bother with the $Q?
Even if both Q and the make-flag needs to be set for some reason, I think the condition for when it needs to be set should be reworked to set both consistently.

[StefanJum]

Indeed @kubanrob, looks like Q just was not set in case V=0. Please take another look now.

[kubanrob]

Thank you @StefanJum!

Reviewed-by: Robert Kuban robert.kuban@opensynergy.com

[mariasfiraiala]

Works as expected, thanks!

Reviewed-by: Maria Sfiraiala maria.sfiraiala@gmail.com

[razvand]

Approved-by: Razvan Deaconescu razvand@unikraft.io