[MacPorts] #60835: /usr/local missing from gcc10 library and include search path

[MacPorts]

#60835: /usr/local missing from gcc10 library and include search path
----------------------+--------------------
  Reporter:  krovetz  |      Owner:  (none)
      Type:  defect   |     Status:  new
  Priority:  Normal   |  Milestone:
 Component:  ports    |    Version:  2.6.2
Resolution:           |   Keywords:
      Port:  gcc10    |
----------------------+--------------------

Comment (by kencu):

 well this goes back forever on MacPorts, right to the beginning of gcc-4.3
 <https://github.com/macports/macports-
 ports/blob/b707f6f84a8207ed7ba244ddbfd827f4431b0695/lang/gcc43/Portfile>

 It was probably done to be "helpful" and avoid pulling in anything in
 /usr/local while automatically including everything in /opt/local.

 In fact, it probably made it much easier to use MacPorts with other non-
 macports software as the macports tree in /opt/local was automatically
 included.

 But it is different than how clang has been configured, certainly, and
 that is not ideal. In a way, it's a shame we can't change our clang builds
 to do this too, but that would make them too differen than xcode clangs.

 I'm not overly inclined to change this just now...how many things might
 break? Every gcc would need to be rebuilt, and some software that links
 properly now might build differently.

 You can pass /usr/local in yourself, of course, if you want to build and
 link against software in there.

-- 
Ticket URL: <https://trac.macports.org/ticket/60835#comment:5>
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