[MacPorts] #54820: missing std::trunc and other std:: math functions when building webkit2-gtk on 10.6 using macports-libsdtc++ and libgcc headers

[MacPorts]

#54820: missing std::trunc and other std:: math functions when building webkit2-gtk
on 10.6 using macports-libsdtc++ and libgcc headers
--------------------------+-------------------------
  Reporter:  kencu        |      Owner:  jeremyhu
      Type:  defect       |     Status:  assigned
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:
Resolution:               |   Keywords:  snowleopard
      Port:  webkit2-gtk  |
--------------------------+-------------------------

Comment (by kencu):

 defining `-std=c99` or `-std=c11` is not something the c++ compiler will
 tolerate, no surprise. I tried instead to add
 {{{
 configure.cxxflags-append -D__STDC_VERSION__=201101L
 }}}
 but that ran into an error due to a weird workaround in the headers for
 gcc 2.95 of all things, involving a `restrict` vs `__restrict` name
 collision. The same test that would enable the long long math functions
 triggers that mess. Maybe there is another way around that.

 I'm starting to see why Apple changed the test to `__DARWIN_NO_LONG_LONG`,
 and why Jeremy just hardwired the definitions into <cmath> rather than
 sort this tangle out. I'll see if there is some tricky way through this,
 but hardwiring them into <cmath> for gcc6 seems like the easiest fix so
 far to me too.

--
Ticket URL: <https://trac.macports.org/ticket/54820#comment:6>
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