> The llvm and pahole generate BTF_INT_BOOL when the dwarf type has
> attribute DW_ATE_boolean.
> But BTF_INT_BOOL is actually used in libbpf to differentiate
> configuration values (CONFIG_* = 'y' vs. CONFIG_* = <value>)
>
> In llvm,
> 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;
> default:
> llvm_unreachable("Unknown BTFTypeInt Encoding");
> }
I just sent a patch to make GCC behave the same way:
https://gcc.gnu.org/pipermail/gcc-patches/2022-July/598702.html
