[Buildroot] [PATCH] package/rust: disable ninja

[Romain Naour]

Hello Arnout,

Le 18/02/2021 à 20:00, Arnout Vandecappelle a écrit :
> 
> 
> On 18/02/2021 00:24, Romain Naour wrote:
>> Ninja has recently be enabled as the default build system to build
>> llvm fork for rust compiler [1]. But we can still use Make if
>> "ninja = false" is provided in config.toml.
>>
>> Ninja support can be enabled by a following patch.
>>
>> [1] https://github.com/rust-lang/rust/commit/30b7dac745b1555cd96f41977f7d24435cbe7fa2
> 
>  That commit reports a speedup of about 2 minutes in build time (on a highly
> parallel system). I guess that on a lowlier system, the build time will still
> improve by more than the 10 seconds it takes to build ninja...

Yes, but the rust package was using Make build system until recently. I'm not
sure if we should switch to ninja for 2021.02 release.

> 
>  So I'd propose to instead just add
> 
> HOST_RUST_DEPENDENCIES += ninja

You mean host-ninja

> 
>  (Note that long-term, I'd like to switch to ninja build for CMake packages in
> general. Not that rust is a cmake package, but llvm is.)

That was already suggested long time ago but the benefit was rather small at
that time:

http://patchwork.ozlabs.org/project/buildroot/patch/20170106223748.2203-1-cedric.marie@openmailbox.org/

Best regards,
Romain


> 
>  Regards,
>  Arnout
> 
>>
>> Fixes:
>> https://gitlab.com/buildroot.org/buildroot/-/jobs/1019386205
>>
>> Signed-off-by: Romain Naour <romain.naour at gmail.com>
>> Cc: Eric Le Bihan <eric.le.bihan.dev at free.fr>
>> ---
>>  package/rust/rust.mk | 2 ++
>>  1 file changed, 2 insertions(+)
>>
>> diff --git a/package/rust/rust.mk b/package/rust/rust.mk
>> index 798450e04e..a38a3d64f5 100644
>> --- a/package/rust/rust.mk
>> +++ b/package/rust/rust.mk
>> @@ -65,6 +65,8 @@ define HOST_RUST_CONFIGURE_CMDS
>>  		echo 'channel = "stable"'; \
>>  		echo '[target.$(RUSTC_TARGET_NAME)]'; \
>>  		echo 'cc = "$(TARGET_CROSS)gcc"'; \
>> +		echo '[llvm]'; \
>> +		echo 'ninja = false'; \
>>  	) > $(@D)/config.toml
>>  endef
>>  
>>