[Bug target/126438] New: Building cross-compiler to powerpc64-apple-darwin9 fails since r17-2606-g2c421a5cbe9d2b

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126438

            Bug ID: 126438
           Summary: Building cross-compiler to powerpc64-apple-darwin9
                    fails since r17-2606-g2c421a5cbe9d2b
           Product: gcc
           Version: 16.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jamborm at gcc dot gnu.org
                CC: jskumari at gcc dot gnu.org
  Target Milestone: ---
              Host: x86_64-linux
            Target: powerpc64-apple-darwin9

Starting with r17-2606-g2c421a5cbe9d2b (Surya Kumari Jangala: rs6000:
Add support for Dense Math Facility (DMF) registers), building a cross
compiler from x86_64-linux to powerpc64-apple-darwin9 (and probably
also to powerpc-apple-darwin9 and powerpc-apple-darwin8) fails with
an ICE in in init_reg_sets, at reginfo.cc:193:

  LC_ALL=C GCC_COLORS= /home/mjambor/gcc/mine/obj/./gcc/xgcc
-B/home/mjambor/gcc/mine/obj/./gcc/  -xc -nostdinc /dev/null -S -o /dev/null
-fself-test=../../src/gcc/testsuite/selftests
  cc1: internal compiler error: in init_reg_sets, at reginfo.cc:193
  0x32dfccc internal_error(char const*, ...)
          ../../src/gcc/diagnostic-global-context.cc:787
  0x32ee633 fancy_abort(char const*, int, char const*)
          ../../src/gcc/diagnostics/context.cc:1813
  0x18bdae9 init_reg_sets()
          ../../src/gcc/reginfo.cc:193
  0x19ae4e7 general_init
          ../../src/gcc/toplev.cc:1156
  /home/mjambor/gcc/mine/obj/./gcc/cc1 -quiet -nostdinc -iprefix
/home/mjambor/gcc/mine/obj/gcc/../lib64/gcc/powerpc64-apple-darwin9/17.0.0/
-isystem /home/mjambor/gcc/mine/obj/./gcc/include -isystem
/home/mjambor/gcc/mine/obj/./gcc/include-fixed -D__DYNAMIC__ /dev/null -fPIC
-quiet -dumpbase null -mmacosx-version-min=10.5
-fself-test=../../src/gcc/testsuite/selftests -o /dev/null
  Please submit a full bug report, with preprocessed source (by using
-freport-bug).
  Please include the complete backtrace with any bug report.


To test yourself, configure GCC with:

  ../src/configure --prefix=/home/mjambor/gcc/mine/inst
--enable-languages=c,c++ --enable-checking=yes --disable-bootstrap
--disable-multilib --enable-obsolete --target=powerpc64-apple-darwin9

and then make the compiler proper with:

  make -j64 all-host CXXFLAGS="-O0 -g" CFLAGS="-O0 -g"