kbuild: simplify silent build (-s) detection

Message ID 1495168096-22440-1-git-send-email-yamada.masahiro@socionext.com
State New
Headers show

Commit Message

Masahiro Yamada May 19, 2017, 4:28 a.m.
This allows to detect -s option without checking GNU Make version.

As commit e36aaea28972 ("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 be the first in a group of short options.
The group could be prefixed with '-'.

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

As commit e6ac89fabd03 ("kbuild: Correctly deal with make options
which contain an 's'") addressed, we also need to deal with long
options that end with '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

We can take care of them, by filtering out long options (--%),
then matching -s% s% %s patterns.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

---

 Makefile | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

-- 
2.7.4

Comments

Michal Marek May 19, 2017, 10:53 a.m. | #1
On 2017-05-19 06:28, Masahiro Yamada wrote:
> This allows to detect -s option without checking GNU Make version.

> 

> As commit e36aaea28972 ("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 be the first in a group of short options.

> The group could be prefixed with '-'.

> 

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

> 

> As commit e6ac89fabd03 ("kbuild: Correctly deal with make options

> which contain an 's'") addressed, we also need to deal with long

> options that end with '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

> 

> We can take care of them, by filtering out long options (--%),

> then matching -s% s% %s patterns.


Good idea, that's a much cleaner way.

Michal

Patch hide | download patch | download mbox

diff --git a/Makefile b/Makefile
index b1ee4a4..d8b5c42 100644
--- a/Makefile
+++ b/Makefile
@@ -84,17 +84,10 @@  endif
 # If the user is running make -s (silent mode), suppress echoing of
 # commands
 
-ifneq ($(filter 4.%,$(MAKE_VERSION)),)	# make-4
-ifneq ($(filter %s ,$(firstword x$(MAKEFLAGS))),)
+ifneq ($(filter -s% s% %s,$(filter-out --%,$(MAKEFLAGS))),)
   quiet=silent_
   tools_silent=s
 endif
-else					# make-3.8x
-ifneq ($(filter s% -s%,$(MAKEFLAGS)),)
-  quiet=silent_
-  tools_silent=-s
-endif
-endif
 
 export quiet Q KBUILD_VERBOSE