https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111812
--- Comment #4 from seurer at gcc dot gnu.org --- I tried a build with r14-4659-ga22eeaca5ce753 and I see the following which looks like it might be the mentioned union issues. g++ -std=gnu++11 -fno-PIE -c -g -O2 -DIN_GCC -fno-exceptions -fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual -Wmissing-format-attribute -Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -fno-common -DHAVE_CONFIG_H -fno-PIE -I. -I. -I/home/seurer/gcc/git/gcc-test/gcc -I/home/seurer/gcc/git/gcc-test/gcc/. -I/home/seurer/gcc/git/gcc-test/gcc/../include -I/home/seurer/gcc/git/gcc-test/gcc/../libcpp/include -I/home/seurer/gcc/git/gcc-test/gcc/../libcody -I/home/seurer/gcc/git/build/gcc-test/./gmp -I/home/seurer/gcc/git/gcc-test/gmp -I/home/seurer/gcc/git/build/gcc-test/./mpfr/src -I/home/seurer/gcc/git/gcc-test/mpfr/src -I/home/seurer/gcc/git/gcc-test/mpc/src -I/home/seurer/gcc/git/gcc-test/gcc/../libdecnumber -I/home/seurer/gcc/git/gcc-test/gcc/../libdecnumber/dpd -I../libdecnumber -I/home/seurer/gcc/git/gcc-test/gcc/../libbacktrace -I/home/seurer/gcc/git/build/gcc-test/./isl/include -I/home/seurer/gcc/git/gcc-test/isl/include -o cse.o -MT cse.o -MMD -MP -MF ./.deps/cse.TPo /home/seurer/gcc/git/gcc-test/gcc/cse.cc In file included from /home/seurer/gcc/git/gcc-test/gcc/cse.cc:25:0: /home/seurer/gcc/git/gcc-test/gcc/rtl.h:66:26: warning: 'rtx_def::code' is too small to hold all values of 'enum rtx_code' [enabled by default] #define RTX_CODE_BITSIZE 8 ^ /home/seurer/gcc/git/gcc-test/gcc/rtl.h:318:33: note: in expansion of macro 'RTX_CODE_BITSIZE' ENUM_BITFIELD(rtx_code) code: RTX_CODE_BITSIZE; ^ /home/seurer/gcc/git/gcc-test/gcc/rtl.h:66:26: warning: 'qty_table_elem::comparison_code' is too small to hold all values of 'enum rtx_code' [enabled by default] #define RTX_CODE_BITSIZE 8 ^ /home/seurer/gcc/git/gcc-test/gcc/cse.cc:252:45: note: in expansion of macro 'RTX_CODE_BITSIZE' ENUM_BITFIELD(rtx_code) comparison_code : RTX_CODE_BITSIZE; ^ /home/seurer/gcc/git/gcc-test/gcc/cse.cc: In function 'void add_to_set(vec<set>*, rtx)': /home/seurer/gcc/git/gcc-test/gcc/cse.cc:4236:23: warning: missing initializer for member 'set::rtl' [-Wmissing-field-initializers] struct set entry = {}; ^ /home/seurer/gcc/git/gcc-test/gcc/cse.cc:4236:23: warning: missing initializer for member 'set::src' [-Wmissing-field-initializers] /home/seurer/gcc/git/gcc-test/gcc/cse.cc:4236:23: warning: missing initializer for member 'set::src_elt' [-Wmissing-field-initializers] /home/seurer/gcc/git/gcc-test/gcc/cse.cc:4236:23: warning: missing initializer for member 'set::src_hash' [-Wmissing-field-initializers] /home/seurer/gcc/git/gcc-test/gcc/cse.cc:4236:23: warning: missing initializer for member 'set::dest_hash' [-Wmissing-field-initializers] /home/seurer/gcc/git/gcc-test/gcc/cse.cc:4236:23: warning: missing initializer for member 'set::inner_dest' [-Wmissing-field-initializers] /home/seurer/gcc/git/gcc-test/gcc/cse.cc:4236:23: warning: missing initializer for member 'set::src_in_memory' [-Wmissing-field-initializers] /home/seurer/gcc/git/gcc-test/gcc/cse.cc:4236:23: warning: missing initializer for member 'set::src_volatile' [-Wmissing-field-initializers] /home/seurer/gcc/git/gcc-test/gcc/cse.cc:4236:23: warning: missing initializer for member 'set::mode' [-Wmissing-field-initializers] /home/seurer/gcc/git/gcc-test/gcc/cse.cc:4236:23: warning: missing initializer for member 'set::src_const_hash' [-Wmissing-field-initializers] /home/seurer/gcc/git/gcc-test/gcc/cse.cc:4236:23: warning: missing initializer for member 'set::src_const' [-Wmissing-field-initializers] /home/seurer/gcc/git/gcc-test/gcc/cse.cc:4236:23: warning: missing initializer for member 'set::src_const_elt' [-Wmissing-field-initializers] /home/seurer/gcc/git/gcc-test/gcc/cse.cc:4236:23: warning: missing initializer for member 'set::dest_addr_elt' [-Wmissing-field-initializers] /home/seurer/gcc/git/gcc-test/gcc/cse.cc: In function 'void cse_insn(rtx_insn*)': /home/seurer/gcc/git/gcc-test/gcc/cse.cc:4954:19: error: use of deleted function 'rtx_def::rtx_def()' struct rtx_def memory_extend_buf; ^ In file included from /home/seurer/gcc/git/gcc-test/gcc/cse.cc:25:0: /home/seurer/gcc/git/gcc-test/gcc/rtl.h:313:38: note: 'rtx_def::rtx_def()' is implicitly deleted because the default definition would be ill-formed: chain_prev ("RTX_PREV (&%h)"))) rtx_def { ^ /home/seurer/gcc/git/gcc-test/gcc/rtl.h:313:38: error: use of deleted function 'rtx_def::u::u()' /home/seurer/gcc/git/gcc-test/gcc/rtl.h:445:9: note: 'rtx_def::u::u()' is implicitly deleted because the default definition would be ill-formed: union u { ^ /home/seurer/gcc/git/gcc-test/gcc/rtl.h:445:9: error: use of deleted function 'rtunion::rtunion()' /home/seurer/gcc/git/gcc-test/gcc/rtl.h:203:7: note: 'rtunion::rtunion()' is implicitly deleted because the default definition would be ill-formed: union rtunion ^ /home/seurer/gcc/git/gcc-test/gcc/rtl.h:207:15: error: union member 'rtunion::rt_subreg' with non-trivial 'poly_int<N, T>::poly_int() [with unsigned int N = 1u; C = short unsigned int]' poly_uint16 rt_subreg; ^ /home/seurer/gcc/git/gcc-test/gcc/rtl.h:445:9: error: use of deleted function 'block_symbol::block_symbol()' union u { ^ /home/seurer/gcc/git/gcc-test/gcc/rtl.h:237:16: note: 'block_symbol::block_symbol()' is implicitly deleted because the default definition would be ill-formed: struct GTY(()) block_symbol { ^ /home/seurer/gcc/git/gcc-test/gcc/rtl.h:237:16: error: use of deleted function 'rtunion::rtunion()' make[2]: *** [cse.o] Error 1