On Wed, Jul 17, 2019 at 03:23:26AM +0000, Gao, Liming wrote: > Leif: > I agree to discuss the behavior first, then review the code logic in > detail. I add my comments below. > > > -----Original Message----- > > From: Leif Lindholm [mailto:leif.lindh...@linaro.org] > > So, first of all - I am entirely happy with dropping the function. > > But I wanted to have it written anyway in case someone came up with a > > really good explanation for why we needed to completely cover the same > > pattern as the code currently in tree: and the situation does not > > relate to python4 or python5 - it relates to picking the latest of > > 2.7, 2.7.6, 3.5, 3.5.2, 3.5,4, 3.7 (which is my interpretation of the > > behaviour of current HEAD). > > > > So basically - I think we need to reach an agreement (with BaseTools > > maintainers, and existing users) about what the behaviour should be. > > > > - What does PYTHON3_ENABLE mean? Is it for probing only, or are we > > setting it for later use by BaseTools? > > PYTHON3_EANBLE is to decide python3 enable or not. It has high priority. > Once it is set, PYTHON_COMMAND will be ignored. > If it is set to TRUE, edksetup.sh will find Python3 in the system, set > PYTHON_COMMAND env. > If it is set to other value, edksetup.sh will find Python2 in the system, > set PYTHON_COMMAND env. > If PYTHON3_EANBLE is not set, PYTHON_COMMAND will be used if PYTHON_COMMAND > is set. > If PYTHON3_EANBLE is not set, and PYTHON_COMMAND is not set, the > default behavior will set PYTHON3_EANBLE to TRUE.
(typo as discussed in other email corrected above (python3->python2)) > So, the default behavior is to use highest version Python3. User can > set PYTHON_COMMAND for their python version. > > > - What should the priority order be when looking for python > > executables? > > Find the high version python. When we enable Python3, we find > Python37 does great performance optimization. > So, we think high version python can bring more benefit. This is where I disagree. As a user/admin, I am no more interested in my build tools deciding I would prefer another python than the default one than I am in they deciding I would prefer another toolchain. If I build a specific commit of edk2 (including BaseTools) from a specific command line, then I expect any subsequent builds to behave identically unless I have reconfigured the system. Installing another version of python without changing the system default shoulds not change that. If I _want_ to use the newly installed python, I can change the python/python2/python3 links. And if I don't want to do that, I can set PYTHON_COMMAND. "We have seen better performance with 3.7" is an excellent argment for suggesting people install, and use, python 3.7. I do not see it as a good argument for always preferring the highest version available. > > - Can we use simply 'python' as the default? > > Based on previous discussion, we recommend to use Python3 as default. If python3 is to be the default, then I see no use for PYTHON3_£NABLE. If PYTHON_COMMAND is set, it should always be respected. If it's not set, python3 is picked in preference anyway. > > - Do we need functionality for more than selecting between > > python2/python3? > > Yes. Find the high version python installed in the system. Best Regards, Leif -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#43893): https://edk2.groups.io/g/devel/message/43893 Mute This Topic: https://groups.io/mt/32495132/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
