Re: ERROR: INT DW_ATE_unsigned_1 Error emitting BTF type

[Yonghong Song]

On 2/5/21 11:24 AM, Arnaldo Carvalho de Melo wrote:
> Em Fri, Feb 05, 2021 at 11:10:08AM -0800, Yonghong Song escreveu:
> > On 2/5/21 11:06 AM, Sedat Dilek wrote:
> > > On Fri, Feb 5, 2021 at 7:53 PM Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote:
> > > Grepping through linux.git/tools I guess some BTF tools/libs need to
> > > know what BTF_INT_UNSIGNED is?
>   
> > BTF_INT_UNSIGNED needs kernel support. Maybe to teach pahole to
> > ignore this for now until kernel infrastructure is ready.
>
> Yeah, I thought about doing that.
>
> > Not sure whether this information will be useful or not
> > for BTF. This needs to be discussed separately.
>
> Maybe search for the rationale for its introduction in DWARF.

In LLVM, we have:
  uint8_t BTFEncoding;
  switch (Encoding) {
  case dwarf::DW_ATE_boolean:
    BTFEncoding = BTF::INT_BOOL;
    break;
  case dwarf::DW_ATE_signed:
  case dwarf::DW_ATE_signed_char:
    BTFEncoding = BTF::INT_SIGNED;
    break;
  case dwarf::DW_ATE_unsigned:
  case dwarf::DW_ATE_unsigned_char:
    BTFEncoding = 0;
    break;

I think DW_ATE_unsigned can be ignored in pahole since
the default encoding = 0. A simple comment is enough.

> - ARnaldo