Re: Support for gcc

[sdf@google.com]

On 12/20, SuHsueyu wrote:
> Hello, I use gcc 12.1.0 to compile a source file:
> t.c
> struct t {
>    int a:2;
>    int b:3;
>    int c:2;
> } g;
> with gcc -c -gbtf t.c
> and try to use libbpf API btf__parse_split, bpf_object__open, and
> bpf_object__open to parse and load into the kernel, but it failed with
> "libbpf: elf: /path/to/t.o is not a valid eBPF object file".

> Is it wrong for me to do so? Due to some constraint, I cannot use
> clang but gcc. How to parse and load gcc compiled object file with
> libbpf?

I haven't used gcc myself, so can't really help. All I can do is to
point you to these two places:

* https://gcc.gnu.org/wiki/BPFBackEnd
* tools/testing/selftests/bpf/Makefile

Maybe try to follow the instructions on that BPFBackEnd page and try
to compile kernel's selftests to see what's missing?