[Bug target/80556] [8 Regression] bootstrap failure for Ada compiler

["cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80556

--- Comment #64 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Iain D Sandoe <iains@gcc.gnu.org>:

https://gcc.gnu.org/g:d4943ce939d9654932624b9ece24c3a474ae4157

commit r12-5418-gd4943ce939d9654932624b9ece24c3a474ae4157
Author: Iain Sandoe <iain@sandoe.co.uk>
Date:   Mon Sep 20 18:41:56 2021 +0100

    Darwin: Rework handling for unwinder code in libgcc_s and specs [PR80556].

    This addresses a long-standing problem where a work-around for an unwinder
    issue (also a regression) regresses other functionality.  The patch
replaces
    several work-arounds with a fix for PR80556 and a work-around for PR88590.

    * The fix for PR80556 requires a bump to the SO name for libgcc_s, since we
    need to remove the unwinder symbols from it.  This would trigger PR88590
    hence the work-around for that.

    * We weaken the symbols for emulated TLS support so that it is possible
    for a DSO linked with static-libgcc to interoperate with a DSO linked with
    libgcc_s.  Likewise main exes.

    * We remove all the gcc-4.2.1 era stubs machinery and workarounds.

    * libgcc is always now linked ahead of libc, which avoids fails where the
    libc (libSystem) builtins implementations are not up to date.

    * The unwinder now always comes from the system
     - for Darwin9 from /usr/lib/libgcc_s.1.dylib
     - for Darwin10 from /usr/lib/libSystem.dylib
     - for Darwin11+ from /usr/lib/system/libunwind.dylib.

     We still insert a shim on Darwin10 to fix an omitted unwind function, but
     the underlying unwinder remains the system one.

    * The work-around for PR88590 has two parts (1) we always link libgcc from
    its convenience lib on affected system versions (avoiding the need to find
    the DSO path); (2) we add and export the emutls functions from DSOs - this
    makes a relatively small (20k) addition to a DSO.  These can be backed out
    when a proper fix for PR88590 is committed.

    For distributions that wish to install a libgcc_s.1.dylib to satisfy
linkage
    from exes that linked against the stubs can use a reexported libgcc_s.1.1
    (since that contains all the symbols that were previously exported via the
     stubs).

    Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>

    gcc/ChangeLog:

            PR target/80556
            * config/darwin-driver.c (darwin_driver_init): Handle exported
            symbols and symbol lists (suppress automatic export of the TLS
            symbols).
            * config/darwin.c (darwin_rename_builtins): Remove workaround.
            * config/darwin.h (LINK_GCC_C_SEQUENCE_SPEC): Likewise.
            (REAL_LIBGCC_SPEC): Handle revised library uses.
            * config/darwin.opt (nodefaultexport): New.
            * config/i386/darwin.h (PR80556_WORKAROUND): Remove.
            * config/i386/darwin32-biarch.h (PR80556_WORKAROUND): Likewise.
            * config/i386/darwin64-biarch.h (PR80556_WORKAROUND): Likewise.

    libgcc/ChangeLog:

            * config.host: Add weak emutls crt to the extra_parts.
            * config/i386/darwin-lib.h (DECLARE_LIBRARY_RENAMES): Remove
            workaround.
            * config/libgcc-libsystem.ver: Add exclude list for the system-
            provided unwinder.
            * config/t-slibgcc-darwin: Bump SO version, remove stubs code.
            * config/i386/libgcc-darwin.10.4.ver: Removed.
            * config/i386/libgcc-darwin.10.5.ver: Removed.
            * config/rs6000/libgcc-darwin.10.4.ver: Removed.
            * config/rs6000/libgcc-darwin.10.5.ver: Removed.
            * config/t-darwin-noeh: New file.

    gcc/testsuite/ChangeLog:

            * gcc.dg/torture/fp-int-convert-timode-3.c: Remove XFAIL.
            * gcc.dg/torture/fp-int-convert-timode-4.c: Likewise.