[OE-core] [PATCH 2/4] ccache.bbclass: Refactor it to make it more reliable

[Martin Hundebøll]

Hi Robert,

Just a small nit-pick below..

On 10/12/2018 03.24, Robert Yang wrote:
> The previous ccache.bbclass has the following problems:
> - It uses host's ccache for native recipes, but this may not work on some
>    hosts, for example, it nerver works on my Ubuntu 14.04.4, there are always
>    build failures (m4-native failed at do_configure, and others will also be
>    failed if I disable CCACHE for m4-native)
> 
> - native/nativesdk/cross/crosssdk recipes use host's ccahe, but target uses
>    ccache-native, this may confuse user.
> 
> - The target recipes may use both host's ccache and ccache-native, this may
>    cause unexpected problems and hard to debug. This is because ccache-native is
>    in SIGGEN_EXCLUDE_SAFE_RECIPE_DEPS, so ccache-native may not be present when
>    rebuild target recipes, and then it would use hosttools/ccache, but the
>    previous ccache files were generated by ccache-native.
> 
> - Target recipes can't use ccache when no ccahe is installed on the host:
>    CCACHE = "${@bb.utils.which(d.getVar('PATH'), 'ccache') and 'ccache '}"
> 
> After refactored:
> All types recipes (native, target and others) will use ccache-native except
> ccache-native's dependencies, host's cache won't be used any more. It is more
> reliable now, which will work everywhere when ccache-native can be built.
> 
> And now we need use "CCACHE_DISABLE = '1'" to disable ccahe for the recipe
> rather than "CCACHE = ''" since we set CCACHE in anonymous function, and
> d.getVar('CCACHE') works after "CCACHE ??=" which is set in bitbake.conf, so we
> can't check whether CCACHE is set or not in anonymous function since it is
> always set. Use CCACHE_DISABLE to disable it would be more clear.
> 
> Signed-off-by: Robert Yang <liezhi.yang at windriver.com>
> ---
>   meta/classes/ccache.bbclass             | 25 ++++++++++++++++++++++---
>   meta/conf/bitbake.conf                  | 21 ++++++++++++++++-----
>   meta/conf/layer.conf                    |  1 -
>   meta/lib/oe/utils.py                    |  3 +++
>   meta/recipes-devtools/ccache/ccache.inc |  2 ++
>   5 files changed, 43 insertions(+), 9 deletions(-)
> 

<snip>

> diff --git a/meta/lib/oe/utils.py b/meta/lib/oe/utils.py
> index 8a584d6..9c41705 100644
> --- a/meta/lib/oe/utils.py
> +++ b/meta/lib/oe/utils.py
> @@ -363,6 +363,9 @@ def host_gcc_version(d, taskcontextonly=False):
>           return
>   
>       compiler = d.getVar("BUILD_CC")
> +    # Get rid of ccache since it is not present when parsing.
> +    if compiler.startswith('ccache '):
> +        compiler = compiler[7:]

You can avoid the if-condition and hard-coded 7-value by doing:

   # Get rid of ccache since it is no present when parsing.
   compiler = d.getVar("BUILD_CC").lstrip("ccache-")

// Martin

>       try:
>           env = os.environ.copy()
>           env["PATH"] = d.getVar("PATH")
> diff --git a/meta/recipes-devtools/ccache/ccache.inc b/meta/recipes-devtools/ccache/ccache.inc
> index 6566328..259c196 100644
> --- a/meta/recipes-devtools/ccache/ccache.inc
> +++ b/meta/recipes-devtools/ccache/ccache.inc
> @@ -9,6 +9,8 @@ LICENSE = "GPLv3+"
>   
>   DEPENDS = "zlib"
>   
> +DEPENDS_class-native = "${CCACHE_NATIVE_DEPENDS}"
> +
>   SRC_URI = "https://download.samba.org/pub/${BPN}/${BP}.tar.xz"
>   
>   inherit autotools
> 

-- 
Kind regards,
Martin Hundebøll
Embedded Linux Consultant

+45 61 65 54 61
martin at geanix.com

Geanix IVS
https://geanix.com
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