diff options
Diffstat (limited to 'elf/rtld.c')
| -rw-r--r-- | elf/rtld.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/elf/rtld.c b/elf/rtld.c index e015477c19..93c45311d4 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -1526,6 +1526,44 @@ cannot allocate TLS data structures for initial thread"); _dl_printf ("\n"); } } + else if (GLRO(dl_debug_mask) & DL_DEBUG_UNUSED) + { + /* Look through the dependencies of the main executable + and determine which of them is not actually + required. */ + struct link_map *l = GL(dl_loaded); + + /* Relocate the main executable. */ + struct relocate_args args = { .l = l, .lazy = GLRO(dl_lazy) }; + _dl_receive_error (print_unresolved, relocate_doit, &args); + + /* This loop depends on the dependencies of the executable to + correspond in number and order to the DT_NEEDED entries. */ + ElfW(Dyn) *dyn = GL(dl_loaded)->l_ld; + bool first = true; + while (dyn->d_tag != DT_NULL) + { + if (dyn->d_tag == DT_NEEDED) + { + l = l->l_next; + + if (!l->l_used) + { + if (first) + { + _dl_printf ("Unused direct dependencies:\n"); + first = false; + } + + _dl_printf ("\t%s\n", l->l_name); + } + } + + ++dyn; + } + + _exit (first != true); + } else if (! GL(dl_loaded)->l_info[DT_NEEDED]) _dl_printf ("\tstatically linked\n"); else @@ -1534,6 +1572,10 @@ cannot allocate TLS data structures for initial thread"); if (l->l_faked) /* The library was not found. */ _dl_printf ("\t%s => not found\n", l->l_libname->name); + else if (l->l_libname->name[0] == '/') + _dl_printf ("\t%s (0x%0*Zx)\n", l->l_libname->name, + (int) sizeof l->l_map_start * 2, + (size_t) l->l_map_start); else _dl_printf ("\t%s => %s (0x%0*Zx)\n", l->l_libname->name, l->l_name, (int) sizeof l->l_map_start * 2, @@ -1962,6 +2004,8 @@ process_dl_debug (const char *dl_debug) | DL_DEBUG_BINDINGS | DL_DEBUG_VERSIONS | DL_DEBUG_IMPCALLS }, { LEN_AND_STR ("statistics"), "display relocation statistics", DL_DEBUG_STATISTICS }, + { LEN_AND_STR ("unused"), "determined unused DSOs", + DL_DEBUG_UNUSED }, { LEN_AND_STR ("help"), "display this help message and exit", DL_DEBUG_HELP }, }; |