On Wed, Jan 23, 2019 at 5:27 PM Andre McCurdy <armccu...@gmail.com> wrote:
>
> On Wed, Jan 23, 2019 at 12:05 PM Khem Raj <raj.k...@gmail.com> wrote:
> >
> > tune files which inherit the arch definitions already define appropriate
> > -mcpu option, which is equivalent of right -march and -mtune combination
>
> And what about machines which inherit an arch definition instead of a
> cpu definition? Is that no longer supported?
I could not find such a machine configuration in several BSP layers I looked at.
Do you know of machine definitions where these files are included
directly in machine configs ?
if so, then we have to either use _remove or introduce a weak variable
to set march only if
mcpu is not set which
>
> > and is preferred since gcc is getting stricter and stricter with option
> > check semantics and can now find incompatible -march and -mcpu options
> > better with every release. It does internal feature consistency check
> > and if it finds out discrepency between what -mcpu would expand to as
> > compared to -march it will flag the options to be incompatible, for
> > naked eye it sounds wrong but gcc would translate -mcpu to a given
> > -march internally and it might not match to what we set in these arch
> > files.
> >
> > The effects are quite subtle, where this can result in configure test
> > failing to compile due to these incompatible options and a feature
> > option getting disabled for a recipe for no reason.
> >
> > e.g. with gcc9 which can now detect that -mcpu=cortex-a5 and
> > -march=armv7-a are incompatible, many features in libstdc++ ends up
> > disabled due to configure check failures e.g. size_t size, ptrdiff_t
> > sizes, which inturn results in compiling libstdc++ with unwanted
> > disabled features.
>
> It would be interesting to see more specific details of this.
These are configure tests which fail when -Werror is in use and is not
limited to libstdc++
it can happen in any package. Since the diagnostic about incompatible
march mcpu pair
is a warning in general, it does not matter, but when we have -Werror
enabled this turns
into error, You can simply try a small helloworld example to see the effects.
>
> > Signed-off-by: Khem Raj <raj.k...@gmail.com>
> > ---
> > meta/conf/machine/include/arm/arch-armv4.inc | 1 -
> > meta/conf/machine/include/arm/arch-armv5.inc | 1 -
> > meta/conf/machine/include/arm/arch-armv6.inc | 1 -
> > meta/conf/machine/include/arm/arch-armv7a.inc | 1 -
> > meta/conf/machine/include/arm/arch-armv7ve.inc | 1 -
> > meta/conf/machine/include/tune-iwmmxt.inc | 2 +-
> > 6 files changed, 1 insertion(+), 6 deletions(-)
> >
> > diff --git a/meta/conf/machine/include/arm/arch-armv4.inc
> > b/meta/conf/machine/include/arm/arch-armv4.inc
> > index 47a7ad2830..52d8ab1e8f 100644
> > --- a/meta/conf/machine/include/arm/arch-armv4.inc
> > +++ b/meta/conf/machine/include/arm/arch-armv4.inc
> > @@ -2,7 +2,6 @@ DEFAULTTUNE ?= "armv4"
> >
> > TUNEVALID[arm] = "Enable ARM instruction set"
> > TUNEVALID[armv4] = "Enable instructions for ARMv4"
> > -TUNE_CCARGS .= "${@bb.utils.contains('TUNE_FEATURES', 'armv4', '
> > -march=armv4t', '', d)}"
> > # enable --fix-v4bx when we have armv4 in TUNE_FEATURES, but then disable
> > it when we have also armv5 or thumb
> > # maybe we should extend bb.utils.contains to support check for any
> > checkvalues in value, now it does
> > # checkvalues.issubset(val) which cannot be used for negative test of foo
> > neither bar in value
> > diff --git a/meta/conf/machine/include/arm/arch-armv5.inc
> > b/meta/conf/machine/include/arm/arch-armv5.inc
> > index f9068af9de..1fe1b6b8e4 100644
> > --- a/meta/conf/machine/include/arm/arch-armv5.inc
> > +++ b/meta/conf/machine/include/arm/arch-armv5.inc
> > @@ -2,7 +2,6 @@ DEFAULTTUNE ?= "armv5"
> >
> > TUNEVALID[armv5] = "Enable instructions for ARMv5"
> > TUNECONFLICTS[armv5] = "armv4"
> > -TUNE_CCARGS .= "${@bb.utils.contains('TUNE_FEATURES', 'armv5', '
> > -march=armv5t${ARMPKGSFX_DSP}', '', d)}"
> > MACHINEOVERRIDES =. "${@bb.utils.contains('TUNE_FEATURES', 'armv5',
> > 'armv5:', '' ,d)}"
> >
> > require conf/machine/include/arm/arch-armv4.inc
> > diff --git a/meta/conf/machine/include/arm/arch-armv6.inc
> > b/meta/conf/machine/include/arm/arch-armv6.inc
> > index 6c838e999c..adb9be8050 100644
> > --- a/meta/conf/machine/include/arm/arch-armv6.inc
> > +++ b/meta/conf/machine/include/arm/arch-armv6.inc
> > @@ -2,7 +2,6 @@ DEFAULTTUNE ?= "armv6hf"
> >
> > TUNEVALID[armv6] = "Enable instructions for ARMv6"
> > TUNECONFLICTS[armv6] = "armv4 armv5"
> > -TUNE_CCARGS .= "${@bb.utils.contains('TUNE_FEATURES', 'armv6', '
> > -march=armv6', '', d)}"
> > MACHINEOVERRIDES =. "${@bb.utils.contains('TUNE_FEATURES', 'armv6',
> > 'armv6:', '' ,d)}"
> >
> > require conf/machine/include/arm/arch-armv5-dsp.inc
> > diff --git a/meta/conf/machine/include/arm/arch-armv7a.inc
> > b/meta/conf/machine/include/arm/arch-armv7a.inc
> > index a2663d8008..09d2c03a5d 100644
> > --- a/meta/conf/machine/include/arm/arch-armv7a.inc
> > +++ b/meta/conf/machine/include/arm/arch-armv7a.inc
> > @@ -3,7 +3,6 @@ ARM_INSTRUCTION_SET ?= "thumb"
> >
> > TUNEVALID[armv7a] = "Enable instructions for ARMv7-a"
> > TUNECONFLICTS[armv7a] = "armv4 armv5 armv6 armv7"
> > -TUNE_CCARGS .= "${@bb.utils.contains('TUNE_FEATURES', 'armv7a', '
> > -march=armv7-a', '', d)}"
> > MACHINEOVERRIDES =. "${@bb.utils.contains('TUNE_FEATURES', 'armv7a',
> > 'armv7a:', '' ,d)}"
> >
> > require conf/machine/include/arm/arch-armv6.inc
> > diff --git a/meta/conf/machine/include/arm/arch-armv7ve.inc
> > b/meta/conf/machine/include/arm/arch-armv7ve.inc
> > index 4d9260fecb..31e334f645 100644
> > --- a/meta/conf/machine/include/arm/arch-armv7ve.inc
> > +++ b/meta/conf/machine/include/arm/arch-armv7ve.inc
> > @@ -2,7 +2,6 @@ DEFAULTTUNE ?= "armv7vethf"
> >
> > TUNEVALID[armv7ve] = "Enable instructions for ARMv7ve"
> > TUNECONFLICTS[armv7ve] = "armv4 armv5 armv6 armv7 armv7a"
> > -TUNE_CCARGS .= "${@bb.utils.contains('TUNE_FEATURES', 'armv7ve', '
> > -march=armv7ve', '', d)}"
> > MACHINEOVERRIDES =. "${@bb.utils.contains('TUNE_FEATURES', 'armv7ve',
> > 'armv7ve:', '' ,d)}"
> >
> > require conf/machine/include/arm/arch-armv7a.inc
> > diff --git a/meta/conf/machine/include/tune-iwmmxt.inc
> > b/meta/conf/machine/include/tune-iwmmxt.inc
> > index f27423cb2e..6e577697cc 100644
> > --- a/meta/conf/machine/include/tune-iwmmxt.inc
> > +++ b/meta/conf/machine/include/tune-iwmmxt.inc
> > @@ -6,7 +6,7 @@ DEFAULTTUNE ?= "iwmmxt"
> > require conf/machine/include/arm/arch-armv5-dsp.inc
> >
> > TUNEVALID[iwmmxt] = "Enable Intel PXA27x specific processor optimizations"
> > -TUNE_CCARGS .= "${@bb.utils.contains('TUNE_FEATURES', 'iwmmxt', '
> > -march=iwmmxt -mcpu=iwmmxt', '', d)}"
> > +TUNE_CCARGS .= "${@bb.utils.contains('TUNE_FEATURES', 'iwmmxt', '
> > -mcpu=iwmmxt', '', d)}"
> >
> > AVAILTUNES += "iwmmxt"
> > ARMPKGARCH_tune-iwmmxt = "iwmmxt"
> > --
> > 2.20.1
> >
> > --
> > _______________________________________________
> > Openembedded-core mailing list
> > Openembedded-core@lists.openembedded.org
> > http://lists.openembedded.org/mailman/listinfo/openembedded-core
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