Re: [PATCH] btf: fix PR debug/112656

[David Faust <david.faust@oracle.com>]

Hi Indu,

On 11/30/23 14:18, Indu Bhagat wrote:
> PR debug/112656 - btf: function prototypes generated with name
> 
> With this patch, all BTF_KIND_FUNC_PROTO will appear anonymous in the
> generated BTF section.
> 
> As noted in the discussion in the bugzilla, the number of
> BTF_KIND_FUNC_PROTO types output varies across targets (BPF with -mco-re
> vs non-BPF targets).  Hence the check in the test case merely checks
> that all BTF_KIND_FUNC_PROTO appear anonymous.

Looks good to me. OK to apply.
Thanks!

> 
> gcc/ChangeLog:
> 
> 	PR debug/112656
>         * btfout.cc (btf_asm_type): Fixup ctti_name for all
> 	BTF types of kind BTF_KIND_FUNC_PROTO.
> 
> gcc/testsuite/ChangeLog:
> 
> 	PR debug/112656
>         * gcc.dg/debug/btf/btf-function-7.c: New test.
> 
> 
> Testing notes:
>   - bootstrapped and reg tested on x86_64
>   - No regressions in btf.exp on BPF target
> 
> ---
>  gcc/btfout.cc                                 |  4 ++++
>  .../gcc.dg/debug/btf/btf-function-7.c         | 19 +++++++++++++++++++
>  2 files changed, 23 insertions(+)
>  create mode 100644 gcc/testsuite/gcc.dg/debug/btf/btf-function-7.c
> 
> diff --git a/gcc/btfout.cc b/gcc/btfout.cc
> index 1c25404b2c0..a5e0d640e19 100644
> --- a/gcc/btfout.cc
> +++ b/gcc/btfout.cc
> @@ -820,6 +820,10 @@ btf_asm_type (ctf_container_ref ctfc, ctf_dtdef_ref dtd)
>  	btf_kind = BTF_KIND_ENUM64;
>     }
>  
> +  /* PR debug/112656.  BTF_KIND_FUNC_PROTO is always anonymous.  */
> +  if (btf_kind == BTF_KIND_FUNC_PROTO)
> +    dtd->dtd_data.ctti_name = 0;
> +
>    dw2_asm_output_data (4, dtd->dtd_data.ctti_name,
>  		       "TYPE %" PRIu64 " BTF_KIND_%s '%s'",
>  		       get_btf_id (dtd->dtd_type), btf_kind_name (btf_kind),
> diff --git a/gcc/testsuite/gcc.dg/debug/btf/btf-function-7.c b/gcc/testsuite/gcc.dg/debug/btf/btf-function-7.c
> new file mode 100644
> index 00000000000..b560dc75650
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/debug/btf/btf-function-7.c
> @@ -0,0 +1,19 @@
> +/* Test BTF for inlined functions.
> +
> +   See PR/112656 - btf: function prototypes generated with name
> +   BTF_KIND_FUNC_PROTO must be anonymous.  */
> +
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -gbtf -dA" } */
> +
> +/* { dg-final { scan-assembler-times "BTF_KIND_FUNC_PROTO ''\\(\[0-9a-z\]*\\)'" 0 } } */
> +
> +static int log_event(const char *event_name, void *dev_ptr)
> +{
> +  return 666;
> +}
> +
> +int foo ()
> +{
> +  return log_event ("foobar", ((void *)0));
> +}