[MacPorts] #65638: libcxx: builds failing for 10.6, blocking downstream ports

[MacPorts]

#65638: libcxx: builds failing for 10.6, blocking downstream ports
---------------------+---------------------------------------
 Reporter:  mascguy  |      Owner:  catap
     Type:  defect   |     Status:  assigned
 Priority:  Normal   |  Milestone:
Component:  ports    |    Version:  2.7.2
 Keywords:  leopard  |       Port:  libcxx clang-11-bootstrap
---------------------+---------------------------------------
 With the latest update to this port, it no longer builds on 10.6 (for
 either x32 or x64). This is, in turn, blocking downstream builds of many
 ports on the 10.6 buildbots.

 On 10.6_x32, this is due to build dep `clang-11-bootstrap`:

 {{{
 Error: Cannot install libcxx for the archs 'i386 x86_64' because
 Error: its dependency clang-11-bootstrap does not build for the required
 archs by default
 Error: and does not have a universal variant.
 }}}

 On 10.6_x64, `cc1plus` is failing, due to the passed compilation
 arguments:

 {{{
 + for FILE in '../src/*.cpp'
 + /usr/bin/g++-4.2 -c -g -O3 -arch i386 -arch ppc
 -I/opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_lang_libcxx/libcxx/work/libcxxabi-5.0.1.src/include
 -I/opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_lang_libcxx/libcxx/work/libcxx-5.0.1.src/include
 -Os -std=c++11 -stdlib=libc++ -nostdinc++ -fstrict-aliasing -Wstrict-
 aliasing=2 -Wsign-conversion -Wshadow -Wconversion -Wunused-variable
 -Wmissing-field-initializers -Wchar-subscripts -Wmismatched-tags
 -Wmissing-braces -Wshorten-64-to-32 -Wsign-compare -Wstrict-aliasing=2
 -Wstrict-overflow=4 -Wunused-parameter -Wnewline-eof
 -D_LIBCPP_BUILDING_LIBRARY -I../include ../src/abort_message.cpp
 cc1plus: error: unrecognized command line option "-Wsign-conversion"
 cc1plus: error: unrecognized command line option "-Wmismatched-tags"
 cc1plus: error: unrecognized command line option "-std=c++11"
 cc1plus: error: unrecognized command line option "-stdlib=libc++"
 cc1plus: error: unrecognized command line option "-Wsign-conversion"
 cc1plus: error: unrecognized command line option "-Wmismatched-tags"
 cc1plus: error: unrecognized command line option "-std=c++11"
 cc1plus: error: unrecognized command line option "-stdlib=libc++"
 lipo: can't figure out the architecture type of:
 libcxx/work/.tmp/ccugYcqV.out
 make: *** [libcxx/work/libcxxabi-5.0.1.src/lib/libc++abi.dylib] Error 1
 }}}

 https://ports.macports.org/port/libcxx/details/

-- 
Ticket URL: <https://trac.macports.org/ticket/65638>
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