On Mon, Mar 23, 2020 at 8:39 AM Richard Biener
<richard.guent...@gmail.com> wrote:
>
> On Mon, Mar 23, 2020 at 4:07 PM Martin Liška <mli...@suse.cz> wrote:
> >
> > Hi.
> >
> > There's a patch draft that will do the proper versioning of API.
>
> Would sth like this be preferred on the binutils side or would
> splitting up the 'def' field via shift&masking better?
>
> @@ -87,25 +87,30 @@ struct ld_plugin_symbol
> {
> char *name;
> char *version;
> - /* This is for compatibility with older ABIs. The older ABI defined
> - only 'def' field. */
> -#ifdef __BIG_ENDIAN__
> - char unused;
> ...
> + int def;
> int visibility;
> uint64_t size;
> char *comdat_key;
> int resolution;
> };
>
> +/* A symbol belonging to an input file managed by the plugin library
> + (version 2). */
> +
> +struct ld_plugin_symbol_v2
> +{
> + char *name;
> + char *version;
> + int def;
> + int visibility;
> + uint64_t size;
> + char *comdat_key;
> + int resolution;
> + char symbol_type;
> + char section_kind;
> + uint16_t unused;
> +};
>
> I think for ease of use you should do
>
> struct ld_plugin_symbol_v2
> {
> ld_plugin_symbol v1_data;
> char symbol_type;
> char section_kind;
> uint16_t unused;
> }
>
> also please avoid 'char', either use uint8_t or
> at least unsigned char. I guess since you're extending
> the type anyway using two plain 'int' would better follow
> the rest of the data structure.
>
> > It's a subject for discussion.
>
> - status = add_symbols_v2 (file->handle, lto_file.symtab.nsyms,
> - lto_file.symtab.syms);
> + {
> + /* Merge symtab::syms and symtab::syms_v2 data. */
> + for (unsigned int i = 0; i < lto_file.symtab.nsyms; i++)
> + {
>
> I think lto-plugin should internally always parse into the "full" format,
> using defaults for entries not in IL files. Only the interfacing with
> the linker should then decide.
Can we use
#if __has_include (<endian.h>)
...
#ifdef __BYTE_ORDER
#if __BYTE_ORDER == __BIG_ENDIAN
...
We support V2 interface only if <endian.h> defines __BYTE_ORDER?
--
H.J.
