Re: [docs] [yocto-docs][PATCH v2 2/2] migration-5.2: add virtual provider change

["Antonin Godard" <antonin.godard@bootlin.com>]

Hi Quentin,

On Fri Jan 31, 2025 at 1:18 PM CET, Quentin Schulz wrote:
> Hi Antonin,
>
> On 1/31/25 12:14 PM, Antonin Godard via lists.yoctoproject.org wrote:
>> The commit 4ccc3bc8266c ("classes/recipes: Switch virtual/XXX-gcc to
>> virtual/cross-cc (and c++/binutils)") in OE-Core changes the
>> virtual/XXX-gcc to virtual/cross-cc (and c++/binutils) syntax. Add it to
>> the migration manual.
>> 
>> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
>> Signed-off-by: Antonin Godard <antonin.godard@bootlin.com>
>> ---
>>   documentation/migration-guides/migration-5.2.rst | 29 ++++++++++++++++++++++++
>>   1 file changed, 29 insertions(+)
>> 
>> diff --git a/documentation/migration-guides/migration-5.2.rst b/documentation/migration-guides/migration-5.2.rst
>> index a60e3e9a8..b29cb2052 100644
>> --- a/documentation/migration-guides/migration-5.2.rst
>> +++ b/documentation/migration-guides/migration-5.2.rst
>> @@ -105,6 +105,35 @@ some obscure bugs.
>>   Any logic based on ``BB_CURRENT_MC`` equalling to ``default`` by default should
>>   be changed to be equal to an empty string.
>>   
>> +Virtual toolchain provider changes
>> +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> +
>> +Support was added for virtual providers on a per-recipe basis for specific
>> +key toolchain providers listed in ``BB_VIRTUAL_RECIPE_PROVIDERS``. As part of
>> +that support, the ``cross`` providers were simplified to remove the triplet
>> +prefix (:term:`TARGET_PREFIX`, :term:`SDK_PREFIX` and :term:`HOST_PREFIX`) and
>> +generalise the naming. Here are example of how references to these variables
>> +should be changed to use the new ``cross`` syntax::
>> +
>> +   virtual/${HOST_PREFIX}binutils -> virtual/cross-binutils
>> +   virtual/${TARGET_PREFIX}binutils -> virtual/cross-binutils
>> +
>> +   virtual/${HOST_PREFIX}gcc -> virtual/cross-cc
>> +   virtual/${TARGET_PREFIX}gcc -> virtual/cross-cc
>> +   virtual/${SDK_PREFIX}gcc -> virtual/nativesdk-cross-cc
>> +
>> +   virtual/${HOST_PREFIX}compilerlibs -> virtual/compilerlibs
>> +   virtual/${TARGET_PREFIX}compilerlibs -> virtual/compilerlibs
>> +   virtual/nativesdk-${SDK_PREFIX}compilerlibs -> virtual/nativesdk-compilerlibs
>> +
>> +   virtual/${TARGET_PREFIX}g++ -> virtual/cross-c++
>> +
>
> I am not sure this rule applies everywhere looking at the commit that 
> makes the change? (see below for related comment)
>
>> +A :term:`PREFERRED_PROVIDER` assignment should be transformed as follows::
>> +
>> +   PREFERRED_PROVIDER_virtual/${TARGET_PREFIX}binutils -> PREFERRED_PROVIDER_virtual/cross-binutils
>> +   PREFERRED_PROVIDER_virtual/${SDK_PREFIX}binutils -> PREFERRED_PROVIDER_virtual/cross-binutils:class-nativesdk
>> +   PREFERRED_PROVIDER_virtual/${SDK_PREFIX}g++ -> PREFERRED_PROVIDER_virtual/nativesdk-cross-c++
>> +
>
> I believe all PREFERRED_PROVIDER would replace TARGET_PREFIX with cross- 
> (and rename gcc to cc, g++ to c++).
>
> SDK_PREFIX would be replace following the same pattern as TARGET_PREFIX 
> except that an override with :class-nativesdk should be provided. Though 
> it seems there's now a second variable for each PREFERRED_PROVIDER which 
> had an SDK_PREFIX, it'll also need nativesdk- prefix added to the same 
> pattern used for TARGET_PREFIX. Except for compilerlibs which only gets 
> the one with the nativesdk- prefix.
>
> c.f. from 90e0a0f7f4536e1aeb311ab2b061be71b4129e4e in poky:
>
> -PREFERRED_PROVIDER_virtual/${SDK_PREFIX}binutils ?= 
> "binutils-crosssdk-${SDK_SYS}"
> -PREFERRED_PROVIDER_virtual/${SDK_PREFIX}gcc = "gcc-crosssdk-${SDK_SYS}"
> -PREFERRED_PROVIDER_virtual/${SDK_PREFIX}g++ = "gcc-crosssdk-${SDK_SYS}"
> -PREFERRED_PROVIDER_virtual/${SDK_PREFIX}compilerlibs = 
> "nativesdk-gcc-runtime"
> +PREFERRED_PROVIDER_virtual/cross-binutils:class-nativesdk ?= 
> "binutils-crosssdk-${SDK_SYS}"
> +PREFERRED_PROVIDER_virtual/cross-cc:class-nativesdk = 
> "gcc-crosssdk-${SDK_SYS}"
> +PREFERRED_PROVIDER_virtual/cross-c++:class-nativesdk = 
> "gcc-crosssdk-${SDK_SYS}"
> +
> +PREFERRED_PROVIDER_virtual/nativesdk-cross-binutils ?= 
> "binutils-crosssdk-${SDK_SYS}"
> +PREFERRED_PROVIDER_virtual/nativesdk-cross-cc = "gcc-crosssdk-${SDK_SYS}"
> +PREFERRED_PROVIDER_virtual/nativesdk-cross-c++ = "gcc-crosssdk-${SDK_SYS}"
> +PREFERRED_PROVIDER_virtual/nativesdk-compilerlibs = "nativesdk-gcc-runtime"
>
> Now looking a bit more into the changes made in this commit, there isn't 
> a simple search and replace that can be used, sometimes it's replacing a 
> variable with one value, sometimes with another. Depends on the recipe 
> the change is made in I guess?

I guess so. It's probably going to be different based on the recipe, but I
wouldn't know how to phrase it here. I just gave some more examples to
illustrate the changes. Any idea on a better way to explain this?

Antonin

-- 
Antonin Godard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com