[glibc] Revert "riscv: Resolve symbols directly for symbols with STO_RISCV_VARIANT_CC."

[Florian Weimer <fw@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=bf88b47ecb54888a789c02fa81aa4ab81ec2f3a5

commit bf88b47ecb54888a789c02fa81aa4ab81ec2f3a5
Author: Florian Weimer <fweimer@redhat.com>
Date:   Sun May 7 14:16:03 2023 +0200

    Revert "riscv: Resolve symbols directly for symbols with STO_RISCV_VARIANT_CC."
    
    This reverts commit 117e8b341c5c0ace8d65feeef136fececb3fdc9c.
    
    Reason for revert: Causes elf/tst-glibcelf and elf/tst-relro-*
    to fail on all architectures.

Diff:
---
 elf/elf.h                    |  7 -------
 manual/platform.texi         |  6 ------
 sysdeps/riscv/dl-dtprocnum.h | 21 ---------------------
 sysdeps/riscv/dl-machine.h   | 26 --------------------------
 4 files changed, 60 deletions(-)

diff --git a/elf/elf.h b/elf/elf.h
index 4f65b5a32d..94ca23c1bb 100644
--- a/elf/elf.h
+++ b/elf/elf.h
@@ -3933,13 +3933,6 @@ enum
 
 #define R_TILEGX_NUM		130
 
-/* RISC-V specific values for the Dyn d_tag field.  */
-#define DT_RISCV_VARIANT_CC	(DT_LOPROC + 1)
-#define DT_RISCV_NUM		2
-
-/* RISC-V specific values for the st_other field.  */
-#define STO_RISCV_VARIANT_CC 0x80
-
 /* RISC-V ELF Flags */
 #define EF_RISCV_RVC 			0x0001
 #define EF_RISCV_FLOAT_ABI 		0x0006
diff --git a/manual/platform.texi b/manual/platform.texi
index 714c07813f..c6ed73cb97 100644
--- a/manual/platform.texi
+++ b/manual/platform.texi
@@ -121,12 +121,6 @@ when it is not allowed, the priority is set to medium.
 @node RISC-V
 @appendixsec RISC-V-specific Facilities
 
-Functions that are lazily bound must be compatible with the standard calling
-convention. When a function is annotated with STO_RISCV_VARIANT_CC, it means
-this function is not compatible with the standard calling convention. The
-dynamic linker will directly resolve it instead of using the lazy binding
-mechanism.
-
 Cache management facilities specific to RISC-V systems that implement the Linux
 ABI are declared in @file{sys/cachectl.h}.
 
diff --git a/sysdeps/riscv/dl-dtprocnum.h b/sysdeps/riscv/dl-dtprocnum.h
deleted file mode 100644
index 281c5aadeb..0000000000
--- a/sysdeps/riscv/dl-dtprocnum.h
+++ /dev/null
@@ -1,21 +0,0 @@
-/* Configuration of lookup functions.  RISC-V version.
-   Copyright (C) 2023 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library.  If not, see
-   <https://www.gnu.org/licenses/>.  */
-
-/* Number of extra dynamic section entries for this architecture.  By
-   default there are none.  */
-#define DT_THISPROCNUM	DT_RISCV_NUM
diff --git a/sysdeps/riscv/dl-machine.h b/sysdeps/riscv/dl-machine.h
index 0e6c0bb155..c0c9bd93ad 100644
--- a/sysdeps/riscv/dl-machine.h
+++ b/sysdeps/riscv/dl-machine.h
@@ -53,9 +53,6 @@
      || (__WORDSIZE == 64 && (type) == R_RISCV_TLS_TPREL64)))	\
    | (ELF_RTYPE_CLASS_COPY * ((type) == R_RISCV_COPY)))
 
-//* Translate a processor specific dynamic tag to the index in l_info array.  */
-#define DT_RISCV(x) (DT_RISCV_##x - DT_LOPROC + DT_NUM)
-
 /* Return nonzero iff ELF header is compatible with the running host.  */
 static inline int __attribute_used__
 elf_machine_matches_host (const ElfW(Ehdr) *ehdr)
@@ -284,29 +281,6 @@ elf_machine_lazy_rel (struct link_map *map, struct r_scope_elem *scope[],
   /* Check for unexpected PLT reloc type.  */
   if (__glibc_likely (r_type == R_RISCV_JUMP_SLOT))
     {
-      if (__glibc_unlikely (map->l_info[DT_RISCV (VARIANT_CC)] != NULL))
-	{
-          /* Check the symbol table for variant CC symbols.  */
-          const Elf_Symndx symndx = ELFW(R_SYM) (reloc->r_info);
-          const ElfW(Sym) *symtab =
-            (const void *)D_PTR (map, l_info[DT_SYMTAB]);
-          const ElfW(Sym) *sym = &symtab[symndx];
-          if (__glibc_unlikely (sym->st_other & STO_RISCV_VARIANT_CC))
-            {
-              /* Avoid lazy resolution of variant CC symbols.  */
-              const struct r_found_version *version = NULL;
-              if (map->l_info[VERSYMIDX (DT_VERSYM)] != NULL)
-                {
-                  const ElfW(Half) *vernum =
-                    (const void *)D_PTR (map, l_info[VERSYMIDX (DT_VERSYM)]);
-                  version = &map->l_versions[vernum[symndx] & 0x7fff];
-                }
-              elf_machine_rela (map, scope, reloc, sym, version, reloc_addr,
-                                skip_ifunc);
-              return;
-            }
-	}
-
       if (__glibc_unlikely (map->l_mach.plt == 0))
 	{
 	  if (l_addr)