Message ID | 20210517070314.1428091-3-masahiroy@kernel.org (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | [1/4] kbuild: merge scripts/mkmakefile to top Makefile | expand |
diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index 82dd1b65b7a8..f247e691562d 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -90,8 +90,13 @@ clean := -f $(srctree)/scripts/Makefile.clean obj echo-cmd = $(if $($(quiet)cmd_$(1)),\ echo ' $(call escsq,$($(quiet)cmd_$(1)))$(echo-why)';) +# sink stdout for 'make -s' + redirect := + quiet_redirect := +silent_redirect := exec >/dev/null; + # printing commands -cmd = @set -e; $(echo-cmd) $(cmd_$(1)) +cmd = @set -e; $(echo-cmd) $($(quiet)redirect) $(cmd_$(1)) ### # if_changed - execute command if any prerequisite is newer than
When building with 'make -s', no output to stdout should be printed. As Arnd Bergmann reported [1], mkimage shows the detailed information of the generated images. I think this should be done by the 'cmd' macro instead of by individual scripts. Insert 'exec >/dev/null;' in order to redirect stdout to /dev/null for silent builds. [Note about this implementation] 'exec >/dev/null;' may look somewhat tricky, but this has a reason. At first, I tried this: cmd = @set -e; $(echo-cmd) $(cmd_$(1)) >/dev/null Appending '>/dev/null' is a commonly used way for redirection, but it would not work if $(cmd_$(1)) itself contains a redirection. For example, cmd_wrap in scripts/Makefile.asm-generic redirects the output from the 'echo' command into the target file. '$(cmd_$(1)) >/dev/null' would be expanded into: echo "#include <asm-generic/$*.h>" > $@ >/dev/null Then, the target file gets empty because the string will go to /dev/null instead of $@. Next, I tried this: cmd = @set -e; $(echo-cmd) { $(cmd_$(1)); } >/dev/null The form above would be expanded into: { echo "#include <asm-generic/$*.h>" > $@; } >/dev/null This works as expected. However, it would be a syntax error if $(cmd_$(1)) is empty. When CONFIG_TRIM_UNUSED_KSYMS is disabled, $(call cmd,gen_ksymdeps) in scripts/Makefile.build would be expanded into: set -e; { ; } >/dev/null ..., which causes an syntax error. The following does not work for the same reason. cmd = @set -e; $(echo-cmd) ( $(cmd_$(1)) ) >/dev/null So, finally I adopted: cmd = @set -e; $(echo-cmd) exec >/dev/null; $(cmd_$(1)) [1]: https://lore.kernel.org/lkml/20210514135752.2910387-1-arnd@kernel.org/ Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> --- scripts/Kbuild.include | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)