[MacPorts] #55415: cmake @3.10.1 does not build on PPC Tiger, Mac OS X 10.4.11, due to various issues building libuv

[MacPorts]

#55415: cmake @3.10.1 does not build on PPC Tiger, Mac OS X 10.4.11, due to various
issues building libuv
------------------------+-----------------------
  Reporter:  ballapete  |      Owner:  michaelld
      Type:  defect     |     Status:  assigned
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:  2.4.2
Resolution:             |   Keywords:  tiger
      Port:  cmake      |
------------------------+-----------------------

Comment (by ballapete):

 Replying to [comment:32 kencu]:

 > {{{
 > cd /Developer/SDKs/MacOSX10.4u.sdk/
 > sudo ln -s /opt .
 > }}}

 This works, somehow:

 {{{
 /opt/local/var/macports/build/_opt_local_var_macports_sources_lil.fr.rsync.macports.org_release_tarballs_ports_devel_cmake/cmake/work/cmake-3.10.3/CMakeFiles/CMakeOutput.log:
 arg [/Developer/SDKs/MacOSX10.4u.sdk] ==> ignore
 /opt/local/var/macports/build/_opt_local_var_macports_sources_lil.fr.rsync.macports.org_release_tarballs_ports_devel_cmake/cmake/work/cmake-3.10.3/CMakeFiles/CMakeOutput.log:
 Library search paths:
 [;/Developer/SDKs/MacOSX10.4u.sdk/opt/local/lib;/Developer/SDKs/MacOSX10.4u.sdk/opt/local/lib;/Developer/SDKs/MacOSX10.4u.sdk/opt/local/lib/gcc6/gcc
 /ppc-apple-
 darwin8/6.4.0;/Developer/SDKs/MacOSX10.4u.sdk/opt/local/lib/gcc6;/Developer/SDKs/MacOSX10.4u.sdk/usr/lib;/Developer/SDKs/MacOSX10.4u.sdk/usr/local/lib]
 /opt/local/var/macports/build/_opt_local_var_macports_sources_lil.fr.rsync.macports.org_release_tarballs_ports_devel_cmake/cmake/work/cmake-3.10.3/CMakeFiles/CMakeOutput.log:
 Framework search paths:
 [;/Developer/SDKs/MacOSX10.4u.sdk/Library/Frameworks/;/Developer/SDKs/MacOSX10.4u.sdk/System/Library/Frameworks/]
 /opt/local/var/macports/build/_opt_local_var_macports_sources_lil.fr.rsync.macports.org_release_tarballs_ports_devel_cmake/cmake/work/cmake-3.10.3/CMakeFiles/CMakeOutput.log:
 collapse library dir [/Developer/SDKs/MacOSX10.4u.sdk/opt/local/lib] ==>
 [/Developer/SDKs/MacOSX10.4u.sdk/opt/local/lib]
 }}}

 but in the end the result is the same. Why is `-isysroot` necessary a all?
 Doesn't the compiler know by heart where its guts can be found?

--
Ticket URL: <https://trac.macports.org/ticket/55415#comment:33>
MacPorts <https://www.macports.org/>
Ports system for macOS