[MacPorts] #56804: arpack now requires a compiler that supports c++11

[MacPorts]

#56804: arpack now requires a compiler that supports c++11
--------------------+----------------------
 Reporter:  kencu   |      Owner:  mamoll
     Type:  defect  |     Status:  assigned
 Priority:  Normal  |  Milestone:
Component:  ports   |    Version:
 Keywords:          |       Port:  arpack
--------------------+----------------------
 arpack now wants c++11 during configure:
 {{{
 checking whether /usr/bin/clang++ supports C++11 features by default... no
 checking whether /usr/bin/clang++ supports C++11 features with
 -std=gnu++11... yes
 }}}

 It somehow seems to build on 10.7 using the system clang and linking
 against libstdc++ [https://build.macports.org/builders/ports-10
 .7_x86_64_legacy-builder/builds/71051/steps/install-port/logs/stdio log],
 but it fails on 10.6.8 [https://build.macports.org/builders/ports-10
 .6_x86_64_legacy-builder/builds/70207/steps/install-port/logs/stdio log].
 {{{
 checking whether /usr/bin/g++-4.2 supports C++11 features by default... no
 checking whether /usr/bin/g++-4.2 supports C++11 features with
 -std=gnu++11... no
 checking whether /usr/bin/g++-4.2 supports C++11 features with
 -std=gnu++0x... no
 configure: error: *** A compiler with support for C++11 language features
 is required.
 }}}

 Probably the best thing would be to add `PortGroup cxx11 1.1` and revbump
 it to update the link libraries for consistency.

-- 
Ticket URL: <https://trac.macports.org/ticket/56804>
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