There is a configure test for assembler support for the
gnu_unique_object symbol type. This support was added in binutils
2.20, so is present in all versions supported for building glibc.
Thus, I think the configure test can be removed; this patch does so.
Now, there is a caveat that the gas NEWS entry refers to this as a
feature for GNU/Linux targets. But the condition is use of
ELFOSABI_GNU or ELFOSABI_NONE. ELFOSABI_GNU covers Hurd as well as
GNU/Linux (as was the case with the older ELFOSABI_LINUX name), and
ELFOSABI_NONE means this is effectively OS-independent. Furthermore,
I think a correct binutils port for any glibc target ought to support
this feature for use with glibc; glibc supports this as an
OS-independent feature (the configure test is only about glibc
testcases).
Tested for x86_64 (testsuite, and that installed shared libraries are
unchanged by the patch).
* configure.ac (libc_cv_asm_unique_object): Remove configure test.
* configure: Regenerated.
* config.h.in (HAVE_ASM_UNIQUE_OBJECT): Remove #undef.
* elf/tst-unique1.c (do_test) [HAVE_ASM_UNIQUE_OBJECT]: Make code
unconditional.
* elf/tst-unique1mod1.c [HAVE_ASM_UNIQUE_OBJECT]: Likewise.
* elf/tst-unique1mod2.c [HAVE_ASM_UNIQUE_OBJECT]: Likewise.
* elf/tst-unique2.c (do_test) [HAVE_ASM_UNIQUE_OBJECT]: Likewise.
(do_test) [!HAVE_ASM_UNIQUE_OBJECT]: Remove conditional code.
* elf/tst-unique2mod1.c [HAVE_ASM_UNIQUE_OBJECT]: Make code
unconditional.
* elf/tst-unique2mod2.c [HAVE_ASM_UNIQUE_OBJECT]: Likewise.
Some symbols have to be identified process-wide by their name. This is
particularly important for some C++ features (e.g., class local static data
and static variables in inline functions). This cannot completely be
implemented with ELF functionality so far. The STB_GNU_UNIQUE binding
helps by ensuring the dynamic linker will always use the same definition for
all symbols with the same name and this binding.
Joseph Myers