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Date:   Fri, 5 Feb 2021 12:28:23 -0300
From:   Arnaldo Carvalho de Melo <acme@kernel.org>
To:     Sedat Dilek <sedat.dilek@gmail.com>
Cc:     Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>,
        dwarves@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        bpf@vger.kernel.org, Jiri Olsa <jolsa@kernel.org>,
        Jan Engelhardt <jengelh@inai.de>,
        Domenico Andreoli <cavok@debian.org>,
        Matthias Schwarzott <zzam@gentoo.org>,
        Andrii Nakryiko <andriin@fb.com>, Yonghong Song <yhs@fb.com>,
        Mark Wieelard <mjw@redhat.com>,
        Paul Moore <paul@paul-moore.com>,
        Ondrej Mosnacek <omosnace@redhat.com>,
        Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= <berrange@redhat.com>,
        Tom Stellard <tstellar@redhat.com>
Subject: Re: ERROR: INT DW_ATE_unsigned_1 Error emitting BTF type
Message-ID: <20210205152823.GD920417@kernel.org>
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Em Fri, Feb 05, 2021 at 04:23:59PM +0100, Sedat Dilek escreveu:
> On Fri, Feb 5, 2021 at 3:41 PM Sedat Dilek <sedat.dilek@gmail.com> wrote:
> >
> > On Fri, Feb 5, 2021 at 3:37 PM Sedat Dilek <sedat.dilek@gmail.com> wrote:
> > >
> > > Hi,
> > >
> > > when building with pahole v1.20 and binutils v2.35.2 plus Clang
> > > v12.0.0-rc1 and DWARF-v5 I see:
> > > ...
> > > + info BTF .btf.vmlinux.bin.o
> > > + [  != silent_ ]
> > > + printf   %-7s %s\n BTF .btf.vmlinux.bin.o
> > >  BTF     .btf.vmlinux.bin.o
> > > + LLVM_OBJCOPY=/opt/binutils/bin/objcopy /opt/pahole/bin/pahole -J
> > > .tmp_vmlinux.btf
> > > [115] INT DW_ATE_unsigned_1 Error emitting BTF type
> > > Encountered error while encoding BTF.
> >
> > Grepping the pahole sources:
> >
> > $ git grep DW_ATE
> > dwarf_loader.c:         bt->is_bool = encoding == DW_ATE_boolean;
> > dwarf_loader.c:         bt->is_signed = encoding == DW_ATE_signed;
> >
> > Missing DW_ATE_unsigned encoding?
> >
> 
> Checked the LLVM sources:
> 
> clang/lib/CodeGen/CGDebugInfo.cpp:    Encoding =
> llvm::dwarf::DW_ATE_unsigned_char;
> clang/lib/CodeGen/CGDebugInfo.cpp:    Encoding = llvm::dwarf::DW_ATE_unsigned;
> clang/lib/CodeGen/CGDebugInfo.cpp:    Encoding =
> llvm::dwarf::DW_ATE_unsigned_fixed;
> clang/lib/CodeGen/CGDebugInfo.cpp:
>   ? llvm::dwarf::DW_ATE_unsigned
> ...
> lld/test/wasm/debuginfo.test:CHECK-NEXT:                DW_AT_encoding
>  (DW_ATE_unsigned)
> 
> So, I will switch from GNU ld.bfd v2.35.2 to LLD-12.

Thanks for the research, probably your conclusion is correct, can you go
the next step and add that part and check if the end result is the
expected one?

- Arnaldo