linux/tools/scripts
Masahiro Yamada 6f0fa58e45 kbuild: simplify silent build (-s) detection
This allows to detect -s (--silent) option without checking GNU Make
version.

As commit e36aaea289 ("kbuild: Fix silent builds with make-4")
pointed out, GNU Make 4.x changed the way/order it presents the
command line options into MAKEFLAGS.

In Make 3.8x, 's' is always the first in a group of short options.
The group may be prefixed with '-' in some cases.

In Make 4.x, 's' is always the last in a group of short options.

As commit e6ac89fabd ("kbuild: Correctly deal with make options
which contain an 's'") addressed, we also need to deal with long
options that contain 's', like --warn-undefined-variables.

Test cases:

[1] command line input:    make --silent
     -> MAKEFLAGS for Make 3.8x:    s
     -> MAKEFLAGS for Make 4.x :    s

[2] command line input:    make -srR
     -> MAKEFLAGS for Make 3.8x:    sRr
     -> MAKEFLAGS for Make 4.x :    rRs

[3] command line input:    make -s -rR --warn-undefined-variables
     -> MAKEFLAGS for Make 3.8x:    --warn-undefined-variables -sRr
     -> MAKEFLAGS for Make 4.x :    rRs --warn-undefined-variables

My idea to cater to all the cases more easily is to filter out long
options (--%), then search 's' with $(findstring ...).  This way will
be more future-proof even if future versions of Make put 's' in the
middle of the group.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-06-06 09:01:12 +09:00
..
Makefile.arch tools build: Fix objtool build with ARCH=x86_64 2016-07-22 16:37:44 -03:00
Makefile.include kbuild: simplify silent build (-s) detection 2017-06-06 09:01:12 +09:00
utilities.mak tools: Move utilities.mak from perf to tools/scripts/ 2016-03-18 13:57:20 -03:00