Compiling with OpenMP support.

Compiling with OpenMP support.

[Michael Craft]

I'm trying to compile GCC 3.4.2 with OpenMP support. How can I enable
this at compile time?

Re: Compiling with OpenMP support.

[Ian Lance Taylor]

Michael Craft <mcraft@peak15.org> writes:

> I'm trying to compile GCC 3.4.2 with OpenMP support. How can I enable
> this at compile time?

gcc 3.4.2 does not support OpenMP.  The first version of gcc which
supported OpenMP was gcc 4.2.

Ian

Re: Compiling with OpenMP support.

[Michael Craft]

Woops, EXTREME TYPO! I meant 4.3.2. I am using GCC 4.3.2.

On Wed, Jan 28, 2009 at 3:54 PM, Ian Lance Taylor <iant@google.com> wrote:
> Michael Craft <mcraft@peak15.org> writes:
>
>> I'm trying to compile GCC 3.4.2 with OpenMP support. How can I enable
>> this at compile time?
>
> gcc 3.4.2 does not support OpenMP.  The first version of gcc which
> supported OpenMP was gcc 4.2.
>
> Ian
>

Re: Compiling with OpenMP support.

[Ian Lance Taylor]

Michael Craft <mcraft@peak15.org> writes:

> On Wed, Jan 28, 2009 at 3:54 PM, Ian Lance Taylor <iant@google.com> wrote:
>> Michael Craft <mcraft@peak15.org> writes:
>>
>>> I'm trying to compile GCC 3.4.2 with OpenMP support. How can I enable
>>> this at compile time?
>>
>> gcc 3.4.2 does not support OpenMP.  The first version of gcc which
>> supported OpenMP was gcc 4.2.
>
> Woops, EXTREME TYPO! I meant 4.3.2. I am using GCC 4.3.2.

Ah.  In that case, use the -fopenmp option.

Ian

Re: Compiling with OpenMP support.

[Michael Craft]

I think you mean to enable OpenMP support on a specific program, use
the -fopenmp option when you are compiling a program. I know this, but
when I do it, it gives me errors about not being able to find libgomp,
like GCC its self was not compiled with OpenMP support. Is there
something I need to do at the time I compile GCC to enable it to
compile OpenMP programs?

Or do you mean something like doing "./configure -fopenmp" or "make
-fopenmp" when I compile GCC?

On Wed, Jan 28, 2009 at 6:16 PM, Ian Lance Taylor <iant@google.com> wrote:
> Michael Craft <mcraft@peak15.org> writes:
>
>> On Wed, Jan 28, 2009 at 3:54 PM, Ian Lance Taylor <iant@google.com> wrote:
>>> Michael Craft <mcraft@peak15.org> writes:
>>>
>>>> I'm trying to compile GCC 3.4.2 with OpenMP support. How can I enable
>>>> this at compile time?
>>>
>>> gcc 3.4.2 does not support OpenMP.  The first version of gcc which
>>> supported OpenMP was gcc 4.2.
>>
>> Woops, EXTREME TYPO! I meant 4.3.2. I am using GCC 4.3.2.
>
> Ah.  In that case, use the -fopenmp option.
>
> Ian
>

Re: Compiling with OpenMP support.

[Ian Lance Taylor]

Michael Craft <mcraft@peak15.org> writes:

> I think you mean to enable OpenMP support on a specific program, use
> the -fopenmp option when you are compiling a program. I know this, but
> when I do it, it gives me errors about not being able to find libgomp,
> like GCC its self was not compiled with OpenMP support. Is there
> something I need to do at the time I compile GCC to enable it to
> compile OpenMP programs?

gcc itself does not use OpenMP.  libgomp is not not used by gcc when
gcc is itself running.  libgomp is used by the program compiled with
-fopenmp.  You do need to use -fopenmp when you are linking your
program, as well as when you are compiling it.  If you are doing that,
I think you need to tell us precisely what you are doing and what
happens when you do it (i.e., cut and paste from your terminal).

Ian