[lttng-dev] userspace-rcu-0.8.6 problems on MacOSX

[Mathieu Desnoyers]

----- Original Message -----
> From: "Alexandre Montplaisir" <alexmonthy at voxpopuli.im>
> To: "Zifei Tong" <soariez at gmail.com>, "Jim Reid" <jim at rfc1035.com>
> Cc: lttng-dev at lists.lttng.org, "Mathieu Desnoyers" <mathieu.desnoyers at efficios.com>
> Sent: Friday, March 13, 2015 5:19:37 PM
> Subject: Re: [lttng-dev] userspace-rcu-0.8.6 problems on MacOSX
> 
> 
> 
> On 2015-03-13 4:59 AM, Zifei Tong wrote:
> >
> > [...]
> > gcc 4.9 from Homebrew works fine. For clang I have to apply a patch to move
> > '__attribute__((__transparent_union__))' after the union declaration.
> > I think this
> > might be a clang bug.
> 
> Indeed, I tested it with clang 3.5 on Linux and it gives the same error
> too. But your patch fixes it (and it keeps working fine with GCC), it
> seems Clang expects the __attribute__ to be after the closing brace. GCC
> accepts both, although they recommend the other way:
> 
> (from https://gcc.gnu.org/onlinedocs/gcc/Type-Attributes.html )
> For an enum, struct or union type, you may specify attributes either
> between the enum, struct or union tag and the name of the type, or just
> past the closing curly brace of the /definition/. The former syntax is
> preferred.
> 
> 
> I don't know what the liburcu maintainers prefer, to keep using GCC's
> recommended syntax, or to make it compilable on current Clang?
> 

Let's go for clang compatibility. Fixed in:

commit 5135c0fd2284e6365bc9d0c53f060b7e946a412f
Author: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
Date:   Sun Mar 15 21:02:13 2015 -0400

    Fix: move transparent union attribute after union declaration for clang
    
    Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>

> >
> >
> >
> >>
> >>
> >> On 2015-03-11 11:50 AM, Jim Reid wrote:
> >>> Hi. There are some problems getting this to compile on MacOSX (10.9.5):
> >>>
> >>> 1) Many of the make regtest tests fail because the time command use
> >>> command line arguments. eg:
> >>>
> >>> ...
> >>> ./test_urcu_lgc 4 4 10 -d 2 -b 32768
> >>> /usr/bin/time: illegal option -- a
> >>> usage: time [-lp] command.
> >>> ...
> 
> I found the culprit, the scripts tests/benchmark/runtests.sh and
> runtests-batch.sh run "time" with -a -o options, with don't exist on
> OSX's implementation. Changing the script to instead use output
> redirection keeps more or less the same output:
> 
> diff --git a/tests/benchmark/runtests-batch.sh
> b/tests/benchmark/runtests-batch.sh
> 
> index 2da1401..3d295fb 100755
> 
> --- a/tests/benchmark/runtests-batch.sh
> 
> +++ b/tests/benchmark/runtests-batch.sh
> 
> @@ -6,7 +6,7 @@ log_file="runall.detail.log"
> 
>   
> 
>   # Check if time bin is non-empty
> 
>   if [ -n "$test_time_bin" ]; then
> 
> -       time_command="$test_time_bin -a -o $log_file"
> 
> +       time_command="$test_time_bin"
> 
>   else
> 
>          time_command=""
> 
>   fi
> 
> @@ -14,6 +14,6 @@ fi
> 
>   #for a in test_urcu_gc test_urcu_gc_mb test_urcu_qsbr_gc; do
> 
>   for a in test_urcu_gc; do
> 
>          echo "./${a} $*" | tee -a "$log_file"
> 
> -       $time_command ./${a} $*
> 
> +       $time_command ./${a} $* 2>> $log_file
> 
>   done
> 

Applied as:

commit 8d11f7cd74968f5baffdbfde8b38d3197ef6865d
Author: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
Date:   Sun Mar 15 21:15:41 2015 -0400

    tests: Use stderr redirection for time output
    
    Allows using Mac OS X time command in tests.
    
    Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
> 
> 
> However, by doing so those tests now hang on my Mac test system (whereas
> before they would get skipped). Is it possible those tests don't even
> work on Mac?

Do they really hang, or just take a very long time to run ?
Can you reproduce this easily ?

> 
> 
> >>>
> >>> 2) The generated Makefiles feed Linuxy linker arguments (-Wl,-rpath==) to
> >>> the compiler.
> >>> I kludged that by manually editing the Makefile(s) to just use -L././libs
> >>> instead. Which would seem to be a better solution in general. YMMV.
> > Apparently, ld in OS X does not support -Wl,-rpath="/foo/bar" syntax,
> > simply replace '='
> > with space like -Wl,-rpath "/foo/bar" did the trick. I can send a
> > patch for this.
> 
> Sure, you could send a patch. It keeps working with GNU's ld too, so I
> assume it would be acceptable.

Fix pushed:

commit 1f2b013ddbde8634c3b3eda921970e37a21ba297
Author: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
Date:   Sun Mar 15 21:09:15 2015 -0400

    Fix: use space after rpath for OS X ld
    
    Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>

Thanks!

Mathieu

> 
> 
> Cheers,
> Alexandre
> 
> >
> > Thanks,
> > Zifei Tong
> >
> >>> Could you please fix these for a future release? Thanks.
> >>>
> >>>
> 
> 

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com