[MacPorts] #49316: R: compilers portgroup, two fixes

[MacPorts]

#49316: R: compilers portgroup, two fixes
--------------------------+---------------------------
  Reporter:  dstrubbe@…   |      Owner:  kjell.konis@…
      Type:  enhancement  |     Status:  new
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:  2.3.4
Resolution:               |   Keywords:  haspatch
      Port:  R            |
--------------------------+---------------------------

Comment (by kjell.konis@…):

 The discussion is in the appendix (C.3.1) of the R Installation and
 Administration manual
 (https://cran.r-project.org/doc/manuals/r-release/R-admin.html#Mavericks-
 and-later). Following the manual is my only real motivation for gcc48 as
 default. If MacPorts has a default fortran compiler then, for me, that's a
 good enough reason to use it for the R port as well.

-- 
Ticket URL: <https://trac.macports.org/ticket/49316#comment:4>
MacPorts <https://www.macports.org/>
Ports system for OS X