[MacPorts] #65539: isl v0.25: Failed to build isl on Macbook Pro osx 10.13.6

[MacPorts]

#65539: isl v0.25: Failed to build isl on Macbook Pro osx 10.13.6
------------------------+--------------------
 Reporter:  Tom-Bertin  |      Owner:  (none)
     Type:  defect      |     Status:  new
 Priority:  Normal      |  Milestone:
Component:  ports       |    Version:  2.7.2
 Keywords:              |       Port:  isl
------------------------+--------------------
 First of all: this is the first time I fill in an issue report. Ever. So
 if I'm not really clear in my explanation, or if I forgot to mention
 certain obvious things (obvious to more experienced users), I apologise
 beforehand.

 While trying to install isl I get the following error messages:

 {{{
 --->  Building isl
 Error: Failed to build isl: command execution failed
 Error: See
 /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_isl/isl/main.log
 for details.
 Error: Follow https://guide.macports.org/#project.tickets if you believe
 there is a bug.
 Error: Processing of port isl failed
 }}}

 I tried several times, but the problem stays. I need this port because
 it's a dependency for gcc, openmpi.
 I need gcc, openmpi, (and others) to successfully install Finite Element
 Analysis programs like Elmerfem, Calculix, etc.

 Am I doing something wrong? Are there other things (packages,
 configurations, ...) I need to have checked before trying to install isl?
 Or is my system outdated and too old?

 My system is:\\
 Macbook Pro late 2011;\\
 OS 10.13.6;\\
 macports base version 2.7.2;

 Things I think are also important mentioning:
 next to macports I also had Homebrew installed. It could be (but I don't
 remember well) that isl and gcc where installed previously via Homebrew,
 but I removed all Homebrew packages, and removed Homebrew from my system.
 The error messages stayed the same, before and after removal of Homebrew.

 Many thanks,

-- 
Ticket URL: <https://trac.macports.org/ticket/65539>
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