https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69025
--- Comment #1 from Gary Funck <gary at intrepid dot com> ---
This can be most easily reproduced by doing a regular configure and make, then
cd-ing into the gcc build directory and forcing a re-compilation of df-scan.c
at -O3.
cd bld/gcc
rm df-scan.o
make CXXFLAGS='-O3 -g' df-scan.o
[...]
In file included from /eng/upc/dev/gary/gupc-gcc-trunk/src/gcc/target.h:53:0,
from /eng/upc/dev/gary/gupc-gcc-trunk/src/gcc/df-scan.c:28:
/eng/upc/dev/gary/gupc-gcc-trunk/src/gcc/df-scan.c: In function ‘void
df_ref_record(df_ref_class, df_collection_rec*, rtx, rtx_def**, basic_block,
df_insn_info*, df_ref_type, int)’:
/eng/upc/dev/gary/gupc-gcc-trunk/src/gcc/hard-reg-set.h:156:44: error: array
subscript is above array bounds [-Werror=array-bounds]
(!!((SET)[(BIT) / UHOST_BITS_PER_WIDE_INT] \
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
/eng/upc/dev/gary/gupc-gcc-trunk/src/gcc/df-scan.c:2536:18: note: in expansion
of macro ‘TEST_HARD_REG_BIT’
else if (!(TEST_HARD_REG_BIT (elim_reg_set, regno)
^~~~~~~~~~~~~~~~~
cc1plus: all warnings being treated as errors
