gcc10-bootstrap: build on 10.5 PPC +universal is not universal

[kencu (Ken)]

building gcc10-bootstrap on 10.5 PPC defaults to +universal.

The build succeeds without intervention, but the noted universal archs recorded are not universal:

$ port -v installed gcc10-bootstrap
The following ports are currently installed:
  gcc10-bootstrap @10.5.0_0+universal (active) requested_variants='' platform='darwin 9' archs='ppc' date='2024-03-21T03:47:22-0700'

and the port is self is inconsistently universal:

$ port contents gcc10-bootstrap | grep bin/ | xargs file
/opt/local/libexec/gcc10-bootstrap/bin/c++:                              Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/cpp:                              Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/g++:                              Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/gcc:                              Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/gcc-ar:                           Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/gcc-nm:                           Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/gcc-ranlib:                       Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/gcov:                             Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/gcov-dump:                        Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/gcov-tool:                        Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/lto-dump:                         Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/powerpc-apple-darwin9-c++:        Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/powerpc-apple-darwin9-g++:        Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/powerpc-apple-darwin9-gcc:        Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/powerpc-apple-darwin9-gcc-10.5.0: Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/powerpc-apple-darwin9-gcc-ar:     Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/powerpc-apple-darwin9-gcc-nm:     Mach-O executable ppc
/opt/local/libexec/gcc10-bootstrap/bin/powerpc-apple-darwin9-gcc-ranlib: Mach-O executable ppc

$ port contents gcc10-bootstrap | grep dylib | xargs file
/opt/local/libexec/gcc10-bootstrap/lib/libatomic.1.dylib:        Mach-O dynamically linked shared library ppc
/opt/local/libexec/gcc10-bootstrap/lib/libatomic.dylib:          Mach-O dynamically linked shared library ppc
/opt/local/libexec/gcc10-bootstrap/lib/libgcc_ehs.1.1.dylib:     Mach-O universal binary with 2 architectures
/opt/local/libexec/gcc10-bootstrap/lib/libgcc_ehs.1.1.dylib (for architecture ppc):	Mach-O dynamically linked shared library ppc
/opt/local/libexec/gcc10-bootstrap/lib/libgcc_ehs.1.1.dylib (for architecture ppc64):	Mach-O 64-bit dynamically linked shared library ppc64
/opt/local/libexec/gcc10-bootstrap/lib/libgcc_s.1.1.dylib:       Mach-O universal binary with 2 architectures
/opt/local/libexec/gcc10-bootstrap/lib/libgcc_s.1.1.dylib (for architecture ppc):	Mach-O dynamically linked shared library ppc
/opt/local/libexec/gcc10-bootstrap/lib/libgcc_s.1.1.dylib (for architecture ppc64):	Mach-O 64-bit dynamically linked shared library ppc64
/opt/local/libexec/gcc10-bootstrap/lib/libgcc_s.1.dylib:         Mach-O universal binary with 2 architectures
/opt/local/libexec/gcc10-bootstrap/lib/libgcc_s.1.dylib (for architecture ppc):	Mach-O dynamically linked shared library ppc
/opt/local/libexec/gcc10-bootstrap/lib/libgcc_s.1.dylib (for architecture ppc64):	Mach-O 64-bit dynamically linked shared library ppc64
/opt/local/libexec/gcc10-bootstrap/lib/libgomp.1.dylib:          Mach-O dynamically linked shared library ppc
/opt/local/libexec/gcc10-bootstrap/lib/libgomp.dylib:            Mach-O dynamically linked shared library ppc
/opt/local/libexec/gcc10-bootstrap/lib/libitm.1.dylib:           Mach-O dynamically linked shared library ppc
/opt/local/libexec/gcc10-bootstrap/lib/libitm.dylib:             Mach-O dynamically linked shared library ppc
/opt/local/libexec/gcc10-bootstrap/lib/libobjc-gnu.4.dylib:      Mach-O dynamically linked shared library ppc
/opt/local/libexec/gcc10-bootstrap/lib/libobjc-gnu.dylib:        Mach-O dynamically linked shared library ppc
/opt/local/libexec/gcc10-bootstrap/lib/libssp.0.dylib:           Mach-O dynamically linked shared library ppc
/opt/local/libexec/gcc10-bootstrap/lib/libssp.dylib:             Mach-O dynamically linked shared library ppc
/opt/local/libexec/gcc10-bootstrap/lib/libstdc++.6.dylib:        Mach-O dynamically linked shared library ppc
/opt/local/libexec/gcc10-bootstrap/lib/libstdc++.6.dylib-gdb.py: ASCII English text
/opt/local/libexec/gcc10-bootstrap/lib/libstdc++.dylib:          Mach-O dynamically linked shared library ppc

macports.conf on this system is stock except that ccache has been enabled:

$ diff -u macports.conf.default macports.conf
--- macports.conf.default	2024-02-14 12:03:59.000000000 -0800
+++ macports.conf	2023-02-25 11:49:26.000000000 -0800
@@ -1,6 +1,9 @@
 # MacPorts system-wide configuration file.
 # Commented-out values are defaults unless otherwise noted.
 
+configureccache     	yes
+ccache_size         	5G
+
 # Directory under which MacPorts should install ports. This must be
 # where MacPorts itself is installed.
 prefix              	/opt/local

so the universal archs are set currently at i386/ppc (which is another ticket to discuss, but that is what they are at present in macports base default configuration).