[MacPorts] #64757: How to enable Cmake to find Boost?

[MacPorts]

#64757: How to enable Cmake to find Boost?
---------------------------+----------------------
  Reporter:  barracuda156  |      Owner:  mascguy
      Type:  request       |     Status:  assigned
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:  2.7.1
Resolution:                |   Keywords:  powerpc
      Port:  cmake         |
---------------------------+----------------------
Changes (by mascguy):

 * status:  new => assigned
 * owner:  (none) => mascguy


Comment:

 Replying to [comment:4 reneeotten]:
 > Replying to [comment:3 barracuda156]:
 > > As an odd effect on 10.5.8, while I specifically have `boost176` in
 port file (and `boost176` is already built even), when I try install my
 port, Macports insists on installing `boost171` instead.
 > >
 > > This did not occur on 10.6 PPC, where `boost176` was used, as
 supposed.
 >
 > not all that surprising if you take a look at the code in the `boost`
 PG:
 > {{{
 > proc boost::default_version {} {
 >     global os.platform os.major
 >     # Pin version on Darwin9 and older to pre-c++11 version (1.71)
 >     if { ${os.platform} eq "darwin" && ${os.major} <= 9 } {
 >         return 1.71
 >     } else {
 >         return 1.76
 >     }
 > }
 > }}}

 While the behavior makes sense in-general, we should also expose an option
 for the fallback version. That way ports can override it, if they really
 want/need to.

 I'm thinking `boost.fallback_version`, which would default to the present
 value (1.71).

-- 
Ticket URL: <https://trac.macports.org/ticket/64757#comment:5>
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