From: Alexei Starovoitov <a...@fb.com> Date: Mon, 1 May 2017 19:49:21 -0700
> On 4/30/17 11:21 AM, David Miller wrote: >> built with: >> >> clang -O2 -target bpfel -g -c x.c -o x.o >> >> readelf can see it just fine: >> >> [davem@localhost binutils]$ ./readelf --debug-dump=loc ./xel.o >> Contents of the .debug_loc section: >> >> Offset Begin End Expression >> 00000000 0000000000000000 0000000000000010 (DW_OP_reg1 (r1)) >> 00000013 <End of list> >> 00000023 0000000000000010 0000000000000020 (DW_OP_constu: >> 590618314553; DW_OP_stack_value) >> 0000003d 0000000000000020 0000000000000030 (DW_OP_reg1 (r1)) >> 00000050 <End of list> >> >> But with big-endian: >> >> [davem@localhost binutils]$ ./readelf --debug-dump=loc ./xeb.o >> readelf: Warning: Invalid pointer size (0) in compunit header, using 4 >> instead >> readelf: Warning: Bogus end-of-siblings marker detected at offset 27 >> in .debug_info section >> readelf: Warning: Bogus end-of-siblings marker detected at offset 28 >> in .debug_info section >> readelf: Warning: DIE at offset 0x29 refers to abbreviation number 48 >> which does not exist >> readelf: Warning: Unable to load/parse the .debug_info section, so >> cannot interpret the .debug_loc section. > > yeah. clang emitted dwarf for big-endian is broken. > This dwarf stuff is too complicated for normal human beings. > The tight packing making debugging it quite painful. But doesn't the CLANG DWARF2 emission code look at the target endianness?
