[OE-core] CMake error? CMAKE_AR-NOTFOUND

[Richard Purdie]

On Wed, 2012-01-25 at 09:31 +0100, Samuel Stirtzel wrote:
> 2012/1/25 Samuel Stirtzel <s.stirtzel at googlemail.com>:
> > 2012/1/24 Richard Purdie <richard.purdie at linuxfoundation.org>:
> >> On Tue, 2012-01-24 at 14:30 +0100, Samuel Stirtzel wrote:
> >>> Hi,
> >>> currently I try to build a native software that needs CMake, it is a
> >>> required tool to cross compile another software.
> >>> An it seems that CMAKE_AR is set to an invalid value (CMAKE_AR-NOTFOUND).
> >>> The cmake.bbclass has no entry about this.
> >>>
> >>> By searching the web, the only information found was that it can be
> >>> set to ${GCC_PATH}/dld.
> >>> As I am usually not working with CMake where can I find the native
> >>> "ar" or "dld" executable in OpenEmbedded?
> >>>
> >>> Using the archiver from my hosts /usr/bin/ar seems to be wrong since
> >>> in cmake.bbclass "set( CMAKE_FIND_ROOT_PATH_MODE_PROGRAM ONLY )"
> >>> prohibits it.
> >>
> >> In the same way the class figures out OECMAKE_C_COMPILER from ${CC}, you
> >> probably need to figure out ar from ${AR} and pass it to the cmake
> >> configuration.
> >>
> >> Note I know very little about cmake so I'm of less help with that
> >> piece ;-).
> >
> > After looking around in all ends of OE-core it shows up that this
> > error is caused by binutils.inc.
> > Finding ar would be no problem itself, but if the binary is not
> > installed or gets deleted after building binutils-native it is
> > impossible to locate it.
> >
> > In binutils.inc do_install:
> > rm ${D}${bindir}/ar ${D}${bindir}/strings
> Sorry I pasted the wrong line, this was for cross compiling.
> From the do_install_virtclass-native:
> # We only want libiberty, libbfd and libopcodes
> rm -rf ${D}${bindir}
> 
> but the effect is still the same..

If you're after a native "ar", you should use ar from the build system
itself. We do build binutils-native for some of its libraries to avoid
some dependencies on the build system but ar is not something
binutils-native should provide, we assume its there as part of the build
systems toolchain.

If you really need a native ar, you need to figure out how to get cmake
to use "ar" from PATH.

I had previously assumed you wanted to use the cross ar.

Cheers,

Richard