[MacPorts] #65532: isl @0.25: builds failing for 10.7 and 10.13; needs fixes for c++17 detection

[MacPorts]

#65532: isl @0.25: builds failing for 10.7 and 10.13; needs fixes for c++17
detection
-------------------------+---------------------------------
  Reporter:  dyne2meter  |      Owner:  MarcusCalhoun-Lopez
      Type:  defect      |     Status:  assigned
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:  2.7.2
Resolution:              |   Keywords:
      Port:  isl         |
-------------------------+---------------------------------

Comment (by barracuda156):

 On 10.5.8 `isl` 0.25 builds fine as `+universal`:
 {{{
 36-249:~ svacchanda$ port -v installed isl
 The following ports are currently installed:
   isl @0.22.1_0 requested_variants='-universal' platform='darwin 9'
 archs='ppc' date='2021-12-22T12:17:44+0800'
   isl @0.22.1_0+universal requested_variants='+universal' platform='darwin
 9' archs='ppc ppc64' date='2021-12-21T10:37:51+0800'
   isl @0.24_1+universal requested_variants='+universal' platform='darwin
 9' archs='ppc ppc64' date='2021-12-29T00:57:53+0800'
   isl @0.25_0+universal (active) requested_variants='+universal'
 platform='darwin 9' archs='ppc ppc64' date='2022-10-07T16:33:48+0800'
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/65532#comment:19>
MacPorts <https://www.macports.org/>
Ports system for macOS