[Vm-dev] benchmarking and recent results

[Göran Krampe]

On 10/05/2013 07:25 PM, Tobias Pape wrote:
> Am 05.10.2013 um 19:07 schrieb Göran Krampe <goran at krampe.se>:
>
>> On 10/05/2013 12:31 PM, Tobias Pape wrote:
>>> Am 05.10.2013 um 11:48 schrieb Göran Krampe <goran at krampe.se>:
>>>> PPS. Also tried using GCC 4.8.1 and 4.9, but then the compiled VM throws "Bus error: 10" at me. Note that it compiles using the switches for clang then... (Esteban and Igor - we need a nice way of switching compiler in CMakeVMMaker!)
>>>
>>> You typically do that with the CMake invocation yourself like in:
>>>
>>> CC="clang -m32" CXX="clang++ -m32" cmake $SRCDIR
>>> cmake --build $BUILDDIR
>>
>> Well, let me just say that the framework building the sources adds lots of switches for compiling the VM and also sometimes adjusts for different plugins etc.
>
> Yes, clearly.
> The point is here, that CMake tries to match make insofar it
> respects the CC and CXX environment variables.
>    That is, when you want to switch the compiler for CMake,
> you announce it by setting the environment variables[1]
> This should  even work when CMake itself is run by a build script, so you
> say
>
>    CC="clang -m32" ./build.sh
>
>
> All other switches should be unaffected by this.

Sure, but that is the whole problem :). The current sources generated by 
the Pharo setup has a range of switches that makes it compile fine with 
clang, specifically made for clang. (on OSX)

Now... if I throw in gcc 4.8.1 or 4.9, it produces a VM that bombs when 
I run it. I suspect it is because the specific combo of switches that 
makes clang dance (and Esteban reportedly did a lot of test-and-try to 
find that specific combo) also makes GCC produce bad VMs.

Granted, it could be some other reason. :)

But it would be nice to keep both sets of "working switches" in the 
code, instead of just a single set.

regards, Göran