@@ -30,8 +30,6 @@ auto
inline void __attribute__ ((unused, always_inline))
elf_get_dynamic_info (struct link_map *l, ElfW(Dyn) *temp)
{
- ElfW(Dyn) *dyn = l->l_ld;
- ElfW(Dyn) **info;
#if __ELF_NATIVE_CLASS == 32
typedef Elf32_Word d_tag_utype;
#elif __ELF_NATIVE_CLASS == 64
@@ -39,39 +37,36 @@ elf_get_dynamic_info (struct link_map *l, ElfW(Dyn) *temp)
#endif
#if !defined RTLD_BOOTSTRAP && !defined STATIC_PIE_BOOTSTRAP
- if (dyn == NULL)
+ if (l->l_ld == NULL)
return;
#endif
- info = l->l_info;
+ ElfW(Dyn) **info = l->l_info;
- while (dyn->d_tag != DT_NULL)
+ for (ElfW(Dyn) *dyn = l->l_ld; dyn->d_tag != DT_NULL; dyn++)
{
+ d_tag_utype i;
+
if ((d_tag_utype) dyn->d_tag < DT_NUM)
- info[dyn->d_tag] = dyn;
+ i = dyn->d_tag;
else if (dyn->d_tag >= DT_LOPROC
&& dyn->d_tag < DT_LOPROC + DT_THISPROCNUM)
- {
- /* This does not violate the array bounds of l->l_info, but
- gcc 4.6 on sparc somehow does not see this. */
- DIAG_PUSH_NEEDS_COMMENT;
- DIAG_IGNORE_NEEDS_COMMENT (4.6,
- "-Warray-bounds");
- info[dyn->d_tag - DT_LOPROC + DT_NUM] = dyn;
- DIAG_POP_NEEDS_COMMENT;
- }
+ i = dyn->d_tag - DT_LOPROC + DT_NUM;
else if ((d_tag_utype) DT_VERSIONTAGIDX (dyn->d_tag) < DT_VERSIONTAGNUM)
- info[VERSYMIDX (dyn->d_tag)] = dyn;
+ i = VERSYMIDX (dyn->d_tag);
else if ((d_tag_utype) DT_EXTRATAGIDX (dyn->d_tag) < DT_EXTRANUM)
- info[DT_EXTRATAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
- + DT_VERSIONTAGNUM] = dyn;
+ i = DT_EXTRATAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
+ + DT_VERSIONTAGNUM;
else if ((d_tag_utype) DT_VALTAGIDX (dyn->d_tag) < DT_VALNUM)
- info[DT_VALTAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
- + DT_VERSIONTAGNUM + DT_EXTRANUM] = dyn;
+ i = DT_VALTAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
+ + DT_VERSIONTAGNUM + DT_EXTRANUM;
else if ((d_tag_utype) DT_ADDRTAGIDX (dyn->d_tag) < DT_ADDRNUM)
- info[DT_ADDRTAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
- + DT_VERSIONTAGNUM + DT_EXTRANUM + DT_VALNUM] = dyn;
- ++dyn;
+ i = DT_ADDRTAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM
+ + DT_VERSIONTAGNUM + DT_EXTRANUM + DT_VALNUM;
+ else
+ continue;
+
+ info[i] = dyn;
}
#define DL_RO_DYN_TEMP_CNT 8
Since commit 2f056e8a5dd4dc0f075413f931e82cede37d1057 "aarch64: define PI_STATIC_AND_HIDDEN", building glibc with gcc-8 on aarch64 fails with /BLD/elf/librtld.os: in function `elf_get_dynamic_info': /SRC/elf/get-dynamic-info.h:70:(.text+0xad8): relocation truncated to fit: R_AARCH64_ADR_PREL_PG_HI21 against symbol `_rtld_local' defined in .data section in /BLD/elf/librtld.os This is a gcc bug: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98618 The bug is fixed on gcc-10 and not yet backported. gcc-9 is affected, but the issue happens to not trigger in glibc, gcc-8 and older seems to miscompile rtld.os. Rewriting the affected code in elf_get_dynamic_info seems to make the issue go away on <= gcc-9. The change makes the logic a bit clearer too (by separating the index computation and array update) and drops an older gcc workaround (since gcc 4.6 is no longer supported). Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> --- elf/get-dynamic-info.h | 41 ++++++++++++++++++----------------------- 1 file changed, 18 insertions(+), 23 deletions(-)