MadGraph5_aMC@NLO

reinstalling lhapdf5

Asked by John Doe on 2021-02-05

I am trying to re-install lhapdf5 to run a legacy code I have. However, the install script aborts immediately after trying to download the tarball.

Apparently, the problem is this: when I execute "install lhapdf5" in MG5 2.6, it tries to download the source as

wget --no-check-certificate https://lhapdf.hepforge.org/downloads/lhapdf-5.9.1.tar.gz

but that path turns out to be wrong, probably outdated. The correct path I think is

wget --no-check-certificate https://lhapdf.hepforge.org/downloads/old/lhapdf-5.9.1.tar.gz

Any help gratefully appreciated.

Question information

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Status:
Solved
For:
MadGraph5_aMC@NLO Edit question
Assignee:
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Solved by:
Olivier Mattelaer
Solved:
2021-02-05
Last query:
2021-02-05
Last reply:
2021-02-05
Best Olivier Mattelaer (olivier-mattelaer) said : #1

Hi,

I have updated the link, it should use the new link at 9h40 (GMT).
Now that for legacy code like this one, you should also use legacy compiler (and potentially legacy OS)
Since it is highly possible that new OS/compiler are not able to handle such old code.

Cheers,

Olivier

> On 5 Feb 2021, at 01:45, John Doe <email address hidden> wrote:
>
> New question #695380 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/695380
>
> I am trying to re-install lhapdf5 to run a legacy code I have. However, the install script aborts immediately after trying to download the tarball.
>
> Apparently, the problem is this: when I execute "install lhapdf5" in MG5 2.6, it tries to download the source as
>
> wget --no-check-certificate https://lhapdf.hepforge.org/downloads/lhapdf-5.9.1.tar.gz
>
> but that path turns out to be wrong, probably outdated. The correct path I think is
>
> wget --no-check-certificate https://lhapdf.hepforge.org/downloads/old/lhapdf-5.9.1.tar.gz
>
> Any help gratefully appreciated.
>
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

John Doe (doje) said : #2

Thanks.

The truth is that mg5 2.6 runs perfectly well either with gfortran-6 or with gfortran-8 with "-std=legacy".

The problem was lhapdf5.

With your updated URL now it downloads fine, but it fails to install properly. This is not necessarily a bug in the installer, it could be something else in my system.

So I installed it manually, and now mg5 recognized it but failed to compile with the error:
.ld: failed to convert GOTPCREL relocation; relink with --no-relax

The solution was to set
LDFLAGS=$(STDLIB) $(MACFLAG) -Wl,--no-relax
in Source/make_opts, and now I can run mg5 2.6 with lhapdf5 all right.

John Doe (doje) said : #3

Thanks Olivier Mattelaer, that solved my question.