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Date: Wed, 24 Aug 2011 09:48:15 +0800
From: Kang Kai <Kai.Kang@windriver.com>
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To: Paul Eggleton <paul.eggleton@linux.intel.com>
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Cc: Patches and discussions about the oe-core layer
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Subject: Re: question about meta/class/qmake-base.bbclass
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On 2011=E5=B9=B408=E6=9C=8823=E6=97=A5 02:46, Paul Eggleton wrote:
> On Monday 22 August 2011 10:42:42 Kang Kai wrote:
>> When I read the file  meta/class/qmake-base.bbclass, I find that that
>> are 2 lines:
>>       unset QMAKESPEC || true
>>       ${OE_QMAKE_QMAKE} -makefile -spec ${QMAKESPEC} -o Makefile
>> $QMAKE_VARSUBST_PRE $AFTER $PROFILES $QMAKE_VARSUBST_POST || die "Erro=
r
>> calling ${OE_QMAKE_QMAKE} on $PROFILES"
>>
>> I am confused that why unset QMAKESPEC first and then use it a argumen=
t
>> for qmake?
> It's not obvious, but think that the difference here is between $QMAKES=
PEC and
> ${QMAKESPEC} - the first one is a reference to an environment variable,=
 the
> second is a reference to an OE/BitBake variable. So "unset QMAKESPEC" i=
s just
> clearing out the environment variable; ${QMAKESPEC} would still have a =
value.
>
> Cheers,
> Paul
>
Hi Paul,

Thanks for your detailed answer.

Regards,
Kai