[MacPorts] #62770: clang++ 11 broken by MacOS 11.3 update

[MacPorts]

#62770: clang++ 11 broken by MacOS 11.3 update
-----------------------+---------------------------
  Reporter:  haberg-1  |      Owner:  jeremyhu
      Type:  defect    |     Status:  closed
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:  2.6.4
Resolution:  fixed     |   Keywords:  bigsur x86_64
      Port:  clang-11  |
-----------------------+---------------------------
Changes (by ken-cunningham-webuse):

 * status:  assigned => closed
 * resolution:   => fixed


Comment:

 In [changeset:"b4d02201add7b3e5758513e2df61a140692ead57/macports-ports"
 b4d02201add7b3e5758513e2df61a140692ead57/macports-ports] (master):
 {{{
 #!ConfigurableCommitTicketReference repository="macports-ports"
 revision="b4d02201add7b3e5758513e2df61a140692ead57"
 clang-11: backport include-next fix

 thanks to @landonf for spelunking this one

 Currently, Clang looks for libc++ headers alongside the installation
 directory of Clang, and it also adds a search path for headers in the
 -isysroot. This is problematic if headers are found in both the toolchain
 and in the sysroot, since #include_next will end up finding the libc++
 headers in the sysroot instead of the intended system headers.

 This patch changes the logic such that if the toolchain contains libc++
 headers, no C++ header paths are added in the sysroot. However, if the
 toolchain does *not* contain libc++ headers, the sysroot is searched as
 usual.

 This should not be a breaking change, since any code that previously
 relied on some libc++ headers being found in the sysroot suffered from
 the #include_next issue described above, which renders any libc++ header
 basically useless.

 closes: https://trac.macports.org/ticket/62770
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/62770#comment:19>
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