[CMake] 138% progress when building both all and not-in-all target?

[Dan Kegel]

For what it's worth, that ld error message I ran into does point to
the linker being run twice concurrently with same commandline.
( See also https://bugzilla.redhat.com/show_bug.cgi?id=809122 )

On Fri, Jun 20, 2014 at 7:35 AM, Leif Walsh <leif.walsh at gmail.com> wrote:
> wow
>
>
> On Fri, Jun 20, 2014 at 10:31 AM, Dan Kegel <dank at kegel.com> wrote:
>>
>> It occurs to me that invoking make on this cmake-generated makefile
>> with two targets and -j4 has indeed triggered a more serious problem,
>> and the build fails nondeterministically with an internal error in ld
>> (presumably because the linker's being invoked twice in parallel on
>> the same file?).
>> See https://bugs.launchpad.net/ubuntu/+source/binutils/+bug/423756
>>
>> On Fri, Jun 20, 2014 at 6:45 AM, Dan Kegel <dank at kegel.com> wrote:
>> > On Fri, Jun 20, 2014 at 3:02 AM, David Cole <dlrdave at aol.com> wrote:
>> >>>> 138%
>> >>>> make -j4 all examples_noinst
>> >>
>> >>> I've seen this too but never noticed a pattern about when it happens.
>> >>
>> >> Does it always happen when naming more than one target with make -j?
>> >>
>> >> I thought you were not supposed to name more than one target with make
>> >> -j...
>> >> (but I don't understand fully exactly why that's a bad thing...)
>> >
>> > make itself certainly doesn't have a bug along these lines; you can make
>> > -j
>> > a hundred targets at once and it won't double-build -- if the Makefile
>> > has proper dependencies.
>> >
>> > I could try to demonstrate the problem with a tiny CMakeLists.txt,
>> > but I'm not sure when I'll have time.
>> > - Dan
>
>
>
>
> --
> Cheers,
> Leif