Patch from Thomas Schwinge.

PR testsuite/109951
* configure.ac: 'AC_SUBST(SYSROOT_CFLAGS_FOR_TARGET)'.
* Makefile.in: Regenerate.
* configure: Likewise.
* testsuite/Makefile.in: Likewise.
* testsuite/lib/libgo.exp (libgo_init): If
'--with-build-sysroot=[...]' was specified, use it for build-tree
testing.
* testsuite/libgo-test-support.exp.in (GOC_UNDER_TEST): Don't set.
(SYSROOT_CFLAGS_FOR_TARGET): Set.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/527755

It turns out to be painful to require linking against -lrt on
GNU/Linux, as that makes it harder to link Go code into C programs.
Instead just call the timer syscalls directly.  That is what the
upstream library does anyhow.

gcc/go/
	* gospec.cc: Revert 2022-02-09 change:
	(RTLIB, RT_LIBRARY): Don't define.
	(lang_specific_driver): Don't add -lrt if linking statically
	on GNU/Linux.

gotools/
	* configure.ac: Revert 2022-02-09 change:
	(RT_LIBS): Don't define.
	* Makefile.am (check-runtime): Don't set GOLIBS to $(RT_LIBS).
	* configure, Makefile.in: Regenerate.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/385475

gotools/
	* Makefile.am (go_cmd_cgo_files): Add ast_go118.go
	(check-go-tool): Copy golang.org/x/tools directories.
	* Makefile.in: Regenerate.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/384695

The previous patch wasn't working everytime. Especially when AR had
"-X32_64", the new .so would replace the default one and not just being
added.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/247377

AIX-style libraries contains both 32 and 64 bit shared objects.
This patch follows the adding of FAT libraries support in other gcc
libraries (libgcc, listdc++, etc).

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/242957

Patch by Maciej W. Rozycki.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/216239

    
    Patch by Maciej W. Rozycki.
    
    Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/206577

From-SVN: r278070

    
    In particular, drop __go_type_descriptors_equal, which is no longer
    used, and will be made obsolete by CL 179598.
    
    Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/179858

From-SVN: r271823

    
    Currently, goroutine switches are implemented with libc
    getcontext/setcontext functions, which saves/restores the machine
    register states and also the signal context. This does more than
    what we need, and performs an expensive syscall.
    
    This CL implements a simplified version of getcontext/setcontext,
    in assembly, that only saves/restores the necessary part, i.e.
    the callee-save registers, and the PC, SP. A simplified version
    of makecontext, written in C, is also added. Currently this is
    only implemented on Linux/AMD64.
    
    Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/178298

From-SVN: r271818

	PR go/89172
    internal/cpu, runtime, runtime/pprof: handle function descriptors
    
    When using PPC64 ELF ABI v1 a function address is not a PC, but is the
    address of a function descriptor.  The first field in the function
    descriptor is the actual PC (see
    http://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi.html#FUNC-DES).
    The libbacktrace library knows about this, and libgo uses actual PC
    values consistently except for the helper function funcPC that appears
    in both runtime and runtime/pprof.
    
    This patch fixes funcPC by recording, in the internal/cpu package,
    whether function descriptors are being used.  We have to check for
    function descriptors using a C compiler check, because GCC can be
    configured using --with-abi to select the ELF ABI to use.
    
    Fixes https://gcc.gnu.org/PR89172
    
    Reviewed-on: https://go-review.googlesource.com/c/162978

From-SVN: r269266