Re: [PATCH bpf-next] libbpf: emit diff of mismatched public API, if any

[Alexei Starovoitov <ast@fb.com>]

On 5/22/19 9:15 AM, Andrii Nakryiko wrote:
> It's easy to have a mismatch of "intended to be public" vs really
> exposed API functions. While Makefile does check for this mismatch, if
> it actually occurs it's not trivial to determine which functions are
> accidentally exposed. This patch dumps out a diff showing what's not
> supposed to be exposed facilitating easier fixing.
> 
> Signed-off-by: Andrii Nakryiko <andriin@fb.com>
> ---
>   tools/lib/bpf/.gitignore | 2 ++
>   tools/lib/bpf/Makefile   | 8 ++++++++
>   2 files changed, 10 insertions(+)
> 
> diff --git a/tools/lib/bpf/.gitignore b/tools/lib/bpf/.gitignore
> index d9e9dec04605..c7306e858e2e 100644
> --- a/tools/lib/bpf/.gitignore
> +++ b/tools/lib/bpf/.gitignore
> @@ -3,3 +3,5 @@ libbpf.pc
>   FEATURE-DUMP.libbpf
>   test_libbpf
>   libbpf.so.*
> +libbpf_global_syms.tmp
> +libbpf_versioned_syms.tmp
> diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
> index f91639bf5650..7e7d6d851713 100644
> --- a/tools/lib/bpf/Makefile
> +++ b/tools/lib/bpf/Makefile
> @@ -204,6 +204,14 @@ check_abi: $(OUTPUT)libbpf.so
>   		     "versioned symbols in $^ ($(VERSIONED_SYM_COUNT))." \
>   		     "Please make sure all LIBBPF_API symbols are"	 \
>   		     "versioned in $(VERSION_SCRIPT)." >&2;		 \
> +		readelf -s --wide $(OUTPUT)libbpf-in.o |		 \
> +		    awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$8}'|   \
> +		    sort -u > $(OUTPUT)libbpf_global_syms.tmp;		 \
> +		readelf -s --wide $(OUTPUT)libbpf.so |			 \
> +		    grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 |		 \
> +		    sort -u > $(OUTPUT)libbpf_versioned_syms.tmp; 	 \
> +		diff -u $(OUTPUT)libbpf_global_syms.tmp			 \
> +		     $(OUTPUT)libbpf_versioned_syms.tmp;		 \
>   		exit 1;							 \

good idea.
how about removing tmp files instead of adding them to .gitignore?