RE: [OE-core] [langdale][master][PATCH] rust: Do not use default compiler flags defined in CC crate

[Peter Kjellerstedt <peter.kjellerstedt@axis.com>]

> -----Original Message-----
> From: openembedded-core@lists.openembedded.org <openembedded-core@lists.openembedded.org> On Behalf Of Richard Purdie
> Sent: den 18 november 2022 17:36
> To: Anton Antonov <Anton.Antonov@arm.com>; openembedded-core@lists.openembedded.org
> Subject: Re: [OE-core] [langdale][master][PATCH] rust: Do not use default compiler flags defined in CC crate
> 
> On Fri, 2022-11-18 at 16:21 +0000, Anton Antonov wrote:
> >   I’ve tested your approach. It doesn’t work for whatever reason.
> > CRATE_CC_NO_DEFAULTS is empty exported for native recipes:
> >
> > $ MACHINE=qemuarm bitbake rust-native -e |grep CRATE_CC_NO_DEFAULTS
> > # $CRATE_CC_NO_DEFAULTS [3 operations]
> > #     [export] "${'1' if d.getVar('CRATE_CC_NO_DEFAULTS') == 'true' else '0'}"
> > export CRATE_CC_NO_DEFAULTS=""
> > # $CRATE_CC_NO_DEFAULTS:class-native
> > CRATE_CC_NO_DEFAULTS:class-native=""
> >
> >
> >   I also tried:
> > CRATE_CC_NO_DEFAULTS[export] = "${@oe.utils.conditional('CRATE_CC_NO_DEFAULTS', '', '0', '1', d)}"
> > with the same result – empty export.
> 
> I think it might need to be 0 or "" instead of '0'. It would be nice if
> we could make False work too but I worry that might not.
> 
> Cheers,
> 
> Richard

None of this will work unless you change the code in bitbake/lib/bb/data.py 
to use d.getVarFlag(var, "export") instead of d.getVarFlag(var, "export", False).
However, I assume that is not wanted given that support for foo[unexport] = "1" 
was introduced to counteract a foo[export] = "1".

//Peter