Arm64/ELF: accept relocations against STN_UNDEF
While only a secondary issue there, the testcase of PR gas/27212 exposes
an oversight in relocation handling: Just like e.g. Arm32, which has a
similar comment and a similar check, relocations against STN_UNDEF have
to be permitted to satisfy the ELF spec.
diff --git a/bfd/elfnn-aarch64.c b/bfd/elfnn-aarch64.c
index c4db1e6..c23cbd3 100644
--- a/bfd/elfnn-aarch64.c
+++ b/bfd/elfnn-aarch64.c
@@ -6946,8 +6946,12 @@
/* An object file might have a reference to a local
undefined symbol. This is a daft object file, but we
- should at least do something about it. */
+ should at least do something about it. NONE and NULL
+ relocations do not use the symbol and are explicitly
+ allowed to use an undefined one, so allow those.
+ Likewise for relocations against STN_UNDEF. */
if (r_type != R_AARCH64_NONE && r_type != R_AARCH64_NULL
+ && r_symndx != STN_UNDEF
&& bfd_is_und_section (sec)
&& ELF_ST_BIND (sym->st_info) != STB_WEAK)
(*info->callbacks->undefined_symbol)
