Forcing ELFv2 abi doesn't work for big-endian mode as this mode has no support for ELFv2. ppc64 linux big-endian is deprecated, it' not unexpected to get such issues. Dropping big-endian support for powerpc could be an option to solve this issue but that will be a drawback for AIX (BE) systems.
regards, Maamoun On Mon, Aug 16, 2021 at 10:54 PM Niels Möller <ni...@lysator.liu.se> wrote: > Stijn Tintel <st...@linux-ipv6.be> writes: > > > I suspect this is because musl doesn't support the ELFv1 ABI on ppc64 at > > all, regardless of endianness. I've tried adding -mabi=elfv2 to CFLAGS, > > to force using the ELFv2 ABI, but the problem persists. Suggestions > welcome. > > I don't know that much about ppc64 abi issues myself. From your > description, it seems clear that it's a linker error, and that object > files corresponding to C source files somehow carry different "abi > version attributes" than object files corresponding to nettle's assembly > source files. > > As you've found, configuring with --disable-assembler works around the > problem, but to solve it properly, we'd need to understand why that is. > The assembler should not be invoked directly, but via the same $(CC) and > $(CFLAGS) as the C compiler. > > You'd need to compare those object files and how they're generated. > Compare the compiler command lines. You could perhaps use gcc -v to see > how gcc invokes the assembler in both cases. You can use gcc -save-temps > to look at the assembly files generated by gcc, and check if they use > some special pseudoops to specify the abi. You can use tools like > objdump or readelf to compare attributes in the object files. > > If you can figure out how to produce object files that are compatible > according to the linker, that may not be sufficient, though. You also > need to tweak the assembly files and related macros and configure checks > to use the right api. See powerpc64/README and powerpc64/machine.m4. As > I understand it, abi is currently selected depending on the endianness, > using v1 for big endian and v2 for little endian. > > It may need a configure test independent of endianness. Maybe there's > some predefined symbol we can check, similar to 32-bit/64-bit ABI checks > on other platforms? You could run something like > > powerpc64-openwrt-linux-musl-gcc -E -dM - </dev/null | sort > > With the powerpc64le-linux-gnu-gcc cross compiler I have, the closest > suspect I see is > > #define _CALL_ELF 2 > > Maybe that's the right thing to check? I don't have a big-endian system > or crosscompiler close at hand, but at least there's a bigendian > powerpc64-linux-gnu cross compile setup in the ci system hosted at gitlab. > > Regards, > /Niels > > -- > Niels Möller. PGP-encrypted email is preferred. Keyid 368C6677. > Internet email is subject to wholesale government surveillance. > _______________________________________________ nettle-bugs mailing list nettle-bugs@lists.lysator.liu.se http://lists.lysator.liu.se/mailman/listinfo/nettle-bugs
