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charset=UTF-8 Content-Transfer-Encoding: 7bit On 11/21/24 21:42, Sami Tolvanen wrote: > The compiler may choose not to emit type information in DWARF for all > aliases, but it's possible for each alias to be exported separately. > To ensure we find type information for the aliases as well, read > {section, address} tuples from the symbol table and match symbols also > by address. > > Signed-off-by: Sami Tolvanen > --- [...] > @@ -82,6 +118,130 @@ struct symbol *symbol_get(const char *name) > return sym; > } > > +typedef void (*elf_symbol_callback_t)(const char *name, GElf_Sym *sym, > + Elf32_Word xndx, void *arg); > + > +static void elf_for_each_global(int fd, elf_symbol_callback_t func, void *arg) > +{ > + size_t sym_size; > + GElf_Shdr shdr_mem; > + GElf_Shdr *shdr; > + Elf_Data *xndx_data = NULL; > + Elf_Scn *scn; > + Elf *elf; > + > + if (elf_version(EV_CURRENT) != EV_CURRENT) > + error("elf_version failed: %s", elf_errmsg(-1)); > + > + elf = elf_begin(fd, ELF_C_READ_MMAP, NULL); > + if (!elf) > + error("elf_begin failed: %s", elf_errmsg(-1)); > + > + scn = elf_nextscn(elf, NULL); > + > + while (scn) { > + shdr = gelf_getshdr(scn, &shdr_mem); > + if (!shdr) > + error("gelf_getshdr failed: %s", elf_errmsg(-1)); > + > + if (shdr->sh_type == SHT_SYMTAB_SHNDX) { > + xndx_data = elf_getdata(scn, NULL); > + if (!xndx_data) > + error("elf_getdata failed: %s", elf_errmsg(-1)); > + break; > + } > + > + scn = elf_nextscn(elf, scn); > + } > + > + sym_size = gelf_fsize(elf, ELF_T_SYM, 1, EV_CURRENT); > + scn = elf_nextscn(elf, NULL); > + > + while (scn) { > + shdr = gelf_getshdr(scn, &shdr_mem); > + if (!shdr) > + error("gelf_getshdr failed: %s", elf_errmsg(-1)); > + > + if (shdr->sh_type == SHT_SYMTAB) { > + unsigned int nsyms; > + unsigned int n; > + Elf_Data *data = elf_getdata(scn, NULL); > + > + if (!data) > + error("elf_getdata failed: %s", elf_errmsg(-1)); > + > + if (shdr->sh_entsize != sym_size) > + error("expected sh_entsize (%lu) to be %zu", > + shdr->sh_entsize, sym_size); > + > + nsyms = shdr->sh_size / shdr->sh_entsize; > + > + for (n = 1; n < nsyms; ++n) { > + const char *name = NULL; > + Elf32_Word xndx = 0; > + GElf_Sym sym_mem; > + GElf_Sym *sym; > + > + sym = gelf_getsymshndx(data, xndx_data, n, > + &sym_mem, &xndx); > + > + if (!sym || > + GELF_ST_BIND(sym->st_info) == STB_LOCAL) > + continue; Doesn't NULL returned by gelf_getsymshndx() indicate an error? If yes then I think it should be reported instead of silently skipping the symbol. With this addressed, feel free to add: Reviewed-by: Petr Pavlu -- Thanks, Petr