ld: Disable ifunc tests on Solaris

ld: Disable ifunc tests on Solaris

A couple of ld ifunc tests currently FAIL on 64-bit Solaris/x86:

FAIL: ld-ifunc/ifunc-10-x86-64
FAIL: ld-ifunc/ifunc-11-x86-64
FAIL: ld-ifunc/ifunc-12-x86-64
FAIL: ld-ifunc/ifunc-13-x86-64
FAIL: ld-ifunc/ifunc-14a-x86-64
FAIL: ld-ifunc/ifunc-14b-x86-64
FAIL: ld-ifunc/ifunc-14c-x86-64
FAIL: ld-ifunc/ifunc-14d-x86-64
FAIL: ld-ifunc/ifunc-14e-x86-64
FAIL: ld-ifunc/ifunc-14f-x86-64
FAIL: ld-ifunc/ifunc-15-x86-64
FAIL: ld-ifunc/ifunc-17a-x86-64
FAIL: ld-ifunc/ifunc-17b-x86-64
FAIL: ld-ifunc/ifunc-2-local-x86-64-now
FAIL: ld-ifunc/ifunc-2-local-x86-64
FAIL: ld-ifunc/ifunc-2-x86-64-now
FAIL: ld-ifunc/ifunc-2-x86-64
FAIL: ld-ifunc/ifunc-20-x86-64
FAIL: ld-ifunc/pr17154-x86-64-now
FAIL: ld-ifunc/pr17154-x86-64

For one, the actual error is weird:

./ld-new: target elf64-x86-64 not found
failed with: <./ld-new: target elf64-x86-64 not found>, no expected output
FAIL: ld-ifunc/ifunc-10-x86-64

although ld -V does report the elf_x86_64 emulation as supported:

$ ./ld/ld-new -V
GNU ld (GNU Binutils) 2.34.50.20200328
  Supported emulations:
   elf_x86_64_sol2
   elf_x86_64
[...]

When using ld -m elf_x86_64_sol2 instead, one of the testcases links
successfully.

However, there's no point in pursuing this: Solaris does not support
ifunc, as can be seen in <sys/elf.h>:

/*
 * GNU/Linux specific symbol type not used by Solaris
 */
#define STT_GNU_IFUNC   10

and never will, given that it has symbol capabilities as solution to
effectively the same problem:

http://www.linker-aliens.org/blogs/rie/entry/symbol_capabilitie/

Therefore this patch disables ifunc testing on Solaris completely by
removing Solaris from binutils/testsuite/lib/binutils-common.exp
(supports_gnu_osabi).  The ifunc part is justified above.  SHF_GNU_MBIND is
in the OS-specific range and conflicts with

#define SHF_SUNW_REALLOC        0x01000000      /* internal: krtld realloc */

While the comment suggests this might be relocatable without too much
problems, the description of mbind (no formal spec AFAICS, just the
comment in the binutils patch submission) strongly suggests that this
isn't relevant to Solaris at all.

Indirectly, clearing supports_gnu_osabi on Solaris disables
supports_gnu_unique.  Again, Solaris <sys/elf.h> has

/*
 * GNU/Linux specific binding not used by Solaris
 */
#define STB_GNU_UNIQUE  10

so this seems the right thing to do.

Afterwards, one can remove the explicit mentions of *-*-solaris2* in
quite a number of (but not all) the ld-ifunc dump file notarget lists.

There's one fallout, though: two gas tests now XPASS because they are
xfail'ed for !supports_gnu_osabi:

XPASS: mbind sections 12
XPASS: mbind section contents 16
XPASS: mbind sections 16
XPASS: mbind section contents 16

To fix that, I've changed

#xfail: ![supports_gnu_osabi]

to notarget.

Tested on x86_64-pc-solaris2.11, i386-pc-solaris2.11,
x86_64-pc-linux-gnu, and i686-pc-linux-gnu.

	ld:
	* testsuite/ld-ifunc/ifunc-10-i386.d: Remove *-*-solaris2* from
	notarget.
	* ifunc-11-i386.d: Likewise.
	* ifunc-12-i386.d: Likewise.
	* ifunc-13-i386.d: Likewise.
	* ifunc-14a-i386.d: Likewise.
	* ifunc-14b-i386.d: Likewise.
	* ifunc-14c-i386.d: Likewise.
	* ifunc-14d-i386.d: Likewise.
	* ifunc-14e-i386.d: Likewise.
	* ifunc-14f-i386.d: Likewise.
	* ifunc-15-i386.d: Likewise.
	* ifunc-16-i386-now.d: Likewise.
	* ifunc-16-i386.d: Likewise.
	* ifunc-17a-i386.d: Likewise.
	* ifunc-17b-i386.d: Likewise.
	* ifunc-18a-i386.d: Likewise.
	* ifunc-18b-i386.d: Likewise.
	* ifunc-19a-i386.d: Likewise.
	* ifunc-19b-i386.d: Likewise.
	* ifunc-2-i386-now.d: Likewise.
	* ifunc-2-i386.d: Likewise.
	* ifunc-2-local-i386-now.d: Likewise.
	* ifunc-2-local-i386.d: Likewise.
	* ifunc-20-i386.d: Likewise.
	* ifunc-21-i386.d: Likewise.
	* ifunc-22-i386.d: Likewise.
	* ifunc-5a-i386.d: Likewise.
	* ifunc-5a-local-i386.d: Likewise.
	* ifunc-5b-i386.d: Likewise.
	* ifunc-5b-local-i386.d: Likewise.
	* ifunc-5r-local-i386.d: Likewise.
	* ifunc-6a-i386.d: Likewise.
	* ifunc-6b-i386.d: Likewise.
	* ifunc-7a-i386.d: Likewise.
	* ifunc-7b-i386.d: Likewise.
	* ifunc-8-i386.d: Likewise.
	* ifunc-9-i386.d: Likewise.
	* pr17154-i386-now.d: Likewise.
	* pr17154-i386.d: Likewise.

	* ifunc-23a-x86.d: Remove notarget.
	* ifunc-24a-x86.d: Likewise.
	* ifunc-25a-x86.d: Likewise.

	gas:
	* testsuite/gas/elf/section12a.d: Use notarget instead of xfail.
	* testsuite/gas/elf/section12b.d: Likewise.
	* testsuite/gas/elf/section16a.d: Likewise.
	* testsuite/gas/elf/section16b.d: Likewise.

	binutils:
	* testsuite/lib/binutils-common.exp (supports_gnu_osabi): Don't
	enable on *-*-solaris*.