[MacPorts] #65867: boost176 @1.76.0_5 does not build on PPC Tiger, Mac OS X 10.4.11, because ld: -rpath can only be used when targeting Mac OS X 10.5 or later

[MacPorts]

#65867: boost176 @1.76.0_5 does not build on PPC Tiger, Mac OS X 10.4.11, because
ld: -rpath can only be used when targeting Mac OS X 10.5 or later
------------------------+-----------------------
  Reporter:  ballapete  |      Owner:  (none)
      Type:  defect     |     Status:  new
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:  2.7.2
Resolution:             |   Keywords:  tiger ppc
      Port:  boost176   |
------------------------+-----------------------

Comment (by ballapete):

 `main.log` contains as line #276:

 {{{
 configure LDFLAGS='-L/opt/local/lib -Wl,-headerpad_max_install_names
 -Wl,-rpath,/opt/local/lib/libgcc -arch ppc'
 }}}

 Isn't this a clear sign that `compilers-1.0.tcl` is faulty? It has:

 {{{
 812 proc compilers::add_gcc_rpath_support {} {
 813     global prefix
 814     set gcc_v [compilers::get_current_gcc_version]
 815     if { ${gcc_v} >= 10 || ${gcc_v} == "devel" } {
 816         configure.ldflags-delete  -Wl,-rpath,${prefix}/lib/libgcc
 817         configure.ldflags-append  -Wl,-rpath,${prefix}/lib/libgcc
 818     }
 819 }
 }}}

 and obviously this code block is executed on `PPC Tiger`. Or am I wrong?
 How can I debug how the `Environment` is built up from which excerpts from
 which file?

-- 
Ticket URL: <https://trac.macports.org/ticket/65867#comment:3>
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