[OE-core] wanting to clarify ASSUME_PROVIDED and SANITY_REQUIRED_UTILITIES

[Paul Eggleton]

On Saturday 11 August 2012 08:38:58 Robert P. J. Day wrote:
>   recently, i know that the entry "git-native" was added to the
> entries in ASSUME_PROVIDED in bitbake.conf:
> 
> ASSUME_PROVIDED = "\
>     bzip2-native \
>     git-native \
>     grep-native \
>     diffstat-native \
>     patch-native \
>     perl-native-runtime \
>     python-native-runtime \
>     tar-native \
>     virtual/libintl-native \
>     "
> 
> ostensibly because it's now reasonable to assume that any sane distro
> should be able to provide an oe-compatible version of git.  so far, so
> good.  but there's this in sanity.bbclass:
> 
> SANITY_REQUIRED_UTILITIES ?= "patch diffstat texi2html makeinfo git
> bzip2 tar gzip gawk chrpath wget cpio"
> 
> how do those two relate to one another?

They don't directly. ASSUME_PROVIDED is just a way of satisfying build-time 
dependencies of native recipes when we know they will always be installed on 
the host; for most of these this is backed up by a check to see if they are 
actually installed using SANITY_REQUIRED_UTILITIES.
 
>   sanity.bbclass appears to list the native tools that *must* exist on
> the dev host, but what if one doesn't?  is it then downloaded and
> built unless it's in "ASSUME_PROVIDED"?

No. If you look at the code in sanity.bbclass you'll see if something in 
SANITY_REQUIRED_UTILITIES is missing you'll get an immediate fatal error.

>   also, is there any convenient way to examine my current dev host to
> see what native utilities are candidates for adding to my local
> ASSUME_PROVIDED?

I think you're on your own there - we recommend you leave ASSUME_PROVIDED as-
is.

Cheers,
Paul

-- 

Paul Eggleton
Intel Open Source Technology Centre