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Reply-To: sedat.dilek@gmail.com
From:   Sedat Dilek <sedat.dilek@gmail.com>
Date:   Fri, 5 Feb 2021 16:23:59 +0100
Message-ID: <CA+icZUVyB3qaqq3pwOyJY_F4V6KU9hdF=AJM_D7iEW4QK4Eo6w@mail.gmail.com>
Subject: Re: ERROR: INT DW_ATE_unsigned_1 Error emitting BTF type
To:     Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>
Cc:     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>,
        =?UTF-8?Q?Daniel_P=2E_Berrang=C3=A9?= <berrange@redhat.com>,
        Tom Stellard <tstellar@redhat.com>
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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.

- Sedat -