https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71208
--- Comment #4 from Hans-Peter Nilsson <hp at gcc dot gnu.org> --- Hmmm. I have problems building gcc-6.1.0 for mmix, by the methods that has worked in the past and to the best of my knowledge are the official ones. First, from a separate directory, I build and install binutils-2.25.1 (as you mentioned this exhibits the same problems as with 2.26 and to avoid mixing up with fallout from the default-init-array change) in a local prefix. The CFLAGS setting is for the anticipated debugging: $ ~/derp/gcctop/pr71208/binutils-2.25.1/configure --prefix ~/derp/gcctop/pr71208/p --target mmix CFLAGS=-g3 $ make all $ make install Then I unpack newlib, rename newlib-2.24 to gcc-6.1.0, unpack gcc-6.1.0 to override common files, and configure, in a separate directory: $ ~/derp/gcctop/pr71208/gcc-6.1.0/configure --prefix ~/derp/gcctop/pr71208/p --target mmix (noting that the binutils installed is picked up by the build machinery) $ make all ... checking for /home/hp/derp/gcctop/pr71208/go/./gcc/xgcc -B/home/hp/derp/gcctop/pr71208/go/./gcc/ -B/home/hp/derp/gcctop/pr71208/p/mmix/bin/ -B/home/hp/derp/gcctop/pr71208/p/mmix/lib/ -isystem /home/hp/derp/gcctop/pr71208/p/mmix/include -isystem /home/hp/derp/gcctop/pr71208/p/mmix/sys-include option to produce PIC... -fPIC -DPIC checking if /home/hp/derp/gcctop/pr71208/go/./gcc/xgcc -B/home/hp/derp/gcctop/pr71208/go/./gcc/ -B/home/hp/derp/gcctop/pr71208/p/mmix/bin/ -B/home/hp/derp/gcctop/pr71208/p/mmix/lib/ -isystem /home/hp/derp/gcctop/pr71208/p/mmix/include -isystem /home/hp/derp/gcctop/pr71208/p/mmix/sys-include PIC flag -fPIC -DPIC works... no checking if /home/hp/derp/gcctop/pr71208/go/./gcc/xgcc -B/home/hp/derp/gcctop/pr71208/go/./gcc/ -B/home/hp/derp/gcctop/pr71208/p/mmix/bin/ -B/home/hp/derp/gcctop/pr71208/p/mmix/lib/ -isystem /home/hp/derp/gcctop/pr71208/p/mmix/include -isystem /home/hp/derp/gcctop/pr71208/p/mmix/sys-include static flag -static works... no checking if /home/hp/derp/gcctop/pr71208/go/./gcc/xgcc -B/home/hp/derp/gcctop/pr71208/go/./gcc/ -B/home/hp/derp/gcctop/pr71208/p/mmix/bin/ -B/home/hp/derp/gcctop/pr71208/p/mmix/lib/ -isystem /home/hp/derp/gcctop/pr71208/p/mmix/include -isystem /home/hp/derp/gcctop/pr71208/p/mmix/sys-include supports -c -o file.o... yes checking if /home/hp/derp/gcctop/pr71208/go/./gcc/xgcc -B/home/hp/derp/gcctop/pr71208/go/./gcc/ -B/home/hp/derp/gcctop/pr71208/p/mmix/bin/ -B/home/hp/derp/gcctop/pr71208/p/mmix/lib/ -isystem /home/hp/derp/gcctop/pr71208/p/mmix/include -isystem /home/hp/derp/gcctop/pr71208/p/mmix/sys-include supports -c -o file.o... (cached) yes checking whether the /home/hp/derp/gcctop/pr71208/go/./gcc/xgcc -B/home/hp/derp/gcctop/pr71208/go/./gcc/ -B/home/hp/derp/gcctop/pr71208/p/mmix/bin/ -B/home/hp/derp/gcctop/pr71208/p/mmix/lib/ -isystem /home/hp/derp/gcctop/pr71208/p/mmix/include -isystem /home/hp/derp/gcctop/pr71208/p/mmix/sys-include linker (/home/hp/derp/gcctop/pr71208/go/./gcc/collect-ld) supports shared libraries... yes checking whether -lc should be explicitly linked in... yes checking dynamic linker characteristics... no checking how to hardcode library paths into programs... immediate checking for shl_load... configure: error: Link tests are not allowed after GCC_NO_EXECUTABLES. make[1]: *** [configure-target-libstdc++-v3] Error 1 oops. Thinking maybe --with-newlib is required "these days", I add that: $ ~/derp/gcctop/pr71208/gcc-6.1.0/configure --prefix ~/derp/gcctop/pr71208/p --target mmix --with-newlib $ make all checking for fenv.h... no checking for complex.h... (cached) no checking for complex.h... (cached) no no checking for ISO C99 support to TR1 in <ctype.h>... no checking for fenv.h... (cached) no no checking for ISO C99 support to TR1 in <stdint.h>... no checking for ISO C99 support to TR1 in <math.h>... no no no checking stdbool.h usability... no checking stdbool.h presence... yes configure: WARNING: stdbool.h: present but cannot be compiled configure: WARNING: stdbool.h: check for missing prerequisite headers? configure: WARNING: stdbool.h: see the Autoconf documentation configure: WARNING: stdbool.h: section "Present But Cannot Be Compiled" configure: WARNING: stdbool.h: proceeding with the compiler's result checking for stdbool.h... no checking stdalign.h usability... no checking stdalign.h presence... yes configure: WARNING: stdalign.h: present but cannot be compiled configure: WARNING: stdalign.h: check for missing prerequisite headers? configure: WARNING: stdalign.h: see the Autoconf documentation configure: WARNING: stdalign.h: section "Present But Cannot Be Compiled" configure: WARNING: stdalign.h: proceeding with the compiler's result checking for stdalign.h... no checking for the value of EOF... configure: error: computing EOF failed make[1]: *** [configure-target-libstdc++-v3] Error 1 (other attempts yielding same result pruned) So, how did you manage to build and install gcc-6.1.0 for mmix in the first place? If you have local patches or work out of a branch rather than the release, please add those details too. ...I'm going to retry using the full tuple (mmix-knuth-mmixware) but if that doesn't work I'm ready to declare gcc-6.1.0 broken for this target.
