This is a backport of https://go.dev/cl/640237 from the main repo.

Fixes PR go/118286

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/640435

Patch from Samuel Thibault.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/623415

Backport https://go.dev/cl/620955 from main repo.  Original description:

    src/runtime/testdata/testprogcgo/threadprof.go contains C code with a
    variable called nullptr.  This conflicts with the nullptr keyword in
    the C23 revision of the C standard (showing up as gccgo test build
    failures when updating GCC to use C23 by default when building C
    code).

    Rename that variable to nullpointer to avoid the clash with the
    keyword (any other name that's not a keyword would work just as well).

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/621059

Patch by Rainer Orth <ro@gcc.gnu.org>.

Fixes PR go/106813

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/581724

<stdbool.h> has been available since C99. Use it rather than defining
our own boolean type and values.

Fixes https://gcc.gnu.org/PR114875

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/582275

	PR go/113668

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/560676

	PR go/113530

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/557655

Otherwise we can't tell the difference between builtin type "any" and
a locally defined type "any".

This will require updates to the gccgo export data parsers in the main
Go repo and the x/tools repo.  These updates are https://go.dev/cl/537195
and https://go.dev/cl/537215.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/536715

The libgo/configure.ac file in upstream GCC was changed in

https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=6a6d3817afa02bbcd2388c8e005da6faf88932f1

This adds an automake conditional that is not used, but will be used
in the future when and if libgo is ported to Darwin.

This CL makes the corresponding change in this repo.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/546435

The gofrontend incorrectly accepted code that was missing a type conversion.
The test case for this is bug518.go in https://go.dev/cl/536537.
Future CLs in this series will detect the type error.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/536638

Recent Darwin versions place contraints on the use of run paths
specified in environment variables.  This breaks some assumptions
in the GCC build.

This change allows the user to configure a Darwin build to use
'@rpath/libraryname.dylib' in library names and then to add an
embedded runpath to executables (and libraries with dependents).

The embedded runpath is added by default unless the user adds
'-nodefaultrpaths' to the link line.

For an installed compiler, it means that any executable built with
that compiler will reference the runtimes installed with the
compiler (equivalent to hard-coding the library path into the name
of the library).

During build-time configurations  any "-B" entries will be added to
the runpath thus the newly-built libraries will be found by exes.

Since the install name is set in libtool, that decision needs to be
available here (but might also cause dependent ones in Makefiles,
so we need to export a conditional).

This facility is not available for Darwin 8 or earlier, however the
existing environment variable runpath does work there.

We default this on for systems where the external DYLD_LIBRARY_PATH
does not work and off for Darwin 8 or earlier.  For systems that can
use either method, if the value is unset, we use the default (which
is currently DYLD_LIBRARY_PATH).

ChangeLog:

	* configure: Regenerate.
	* configure.ac: Do not add default runpaths to GCC exes
	when we are building -static-libstdc++/-static-libgcc (the
	default).
	* libtool.m4: Add 'enable-darwin-at-runpath'.  Act  on the
	enable flag to alter Darwin libraries to use @rpath names.

gcc/ChangeLog:

	* aclocal.m4: Regenerate.
	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths.
	* config/darwin.h: Handle Darwin rpaths.
	* config/darwin.opt: Handle Darwin rpaths.
	* Makefile.in:  Handle Darwin rpaths.

gcc/ada/ChangeLog:

	* gcc-interface/Makefile.in: Handle Darwin rpaths.

gcc/jit/ChangeLog:
	* Make-lang.in: Handle Darwin rpaths.

libatomic/ChangeLog:

	* Makefile.am: Handle Darwin rpaths.
	* Makefile.in: Regenerate.
	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths.

libbacktrace/ChangeLog:

	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths.

libcc1/ChangeLog:

	* configure: Regenerate.

libffi/ChangeLog:

	* Makefile.am: Handle Darwin rpaths.
	* Makefile.in: Regenerate.
	* configure: Regenerate.

libgcc/ChangeLog:

	* config/t-slibgcc-darwin: Generate libgcc_s
	with an @rpath name.
	* config.host: Handle Darwin rpaths.

libgfortran/ChangeLog:

	* Makefile.am: Handle Darwin rpaths.
	* Makefile.in: Regenerate.
	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths

libgm2/ChangeLog:

	* Makefile.am: Handle Darwin rpaths.
	* Makefile.in: Regenerate.
	* aclocal.m4: Regenerate.
	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths.
	* libm2cor/Makefile.am: Handle Darwin rpaths.
	* libm2cor/Makefile.in: Regenerate.
	* libm2iso/Makefile.am: Handle Darwin rpaths.
	* libm2iso/Makefile.in: Regenerate.
	* libm2log/Makefile.am: Handle Darwin rpaths.
	* libm2log/Makefile.in: Regenerate.
	* libm2min/Makefile.am: Handle Darwin rpaths.
	* libm2min/Makefile.in: Regenerate.
	* libm2pim/Makefile.am: Handle Darwin rpaths.
	* libm2pim/Makefile.in: Regenerate.

libgomp/ChangeLog:

	* Makefile.am: Handle Darwin rpaths.
	* Makefile.in: Regenerate.
	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths

libitm/ChangeLog:

	* Makefile.am: Handle Darwin rpaths.
	* Makefile.in: Regenerate.
	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths.

libobjc/ChangeLog:

	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths.

libphobos/ChangeLog:

	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths.
	* libdruntime/Makefile.am: Handle Darwin rpaths.
	* libdruntime/Makefile.in: Regenerate.
	* src/Makefile.am: Handle Darwin rpaths.
	* src/Makefile.in: Regenerate.

libquadmath/ChangeLog:

	* Makefile.am: Handle Darwin rpaths.
	* Makefile.in: Regenerate.
	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths.

libsanitizer/ChangeLog:

	* asan/Makefile.am: Handle Darwin rpaths.
	* asan/Makefile.in: Regenerate.
	* configure: Regenerate.
	* hwasan/Makefile.am: Handle Darwin rpaths.
	* hwasan/Makefile.in: Regenerate.
	* lsan/Makefile.am: Handle Darwin rpaths.
	* lsan/Makefile.in: Regenerate.
	* tsan/Makefile.am: Handle Darwin rpaths.
	* tsan/Makefile.in: Regenerate.
	* ubsan/Makefile.am: Handle Darwin rpaths.
	* ubsan/Makefile.in: Regenerate.

libssp/ChangeLog:

	* Makefile.am: Handle Darwin rpaths.
	* Makefile.in: Regenerate.
	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths.

libstdc++-v3/ChangeLog:

	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths.
	* src/Makefile.am: Handle Darwin rpaths.
	* src/Makefile.in: Regenerate.

libvtv/ChangeLog:

	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths.

lto-plugin/ChangeLog:
	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths.

zlib/ChangeLog:
	* configure: Regenerate.
	* configure.ac: Handle Darwin rpaths.

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

Handle the AR environment variable, used by gccgo,
the same way we handle the CC environment variable.

This ports https://go.dev/cl/526275 to the gofrontend repo.

This is needed for gccgo testing because the top-level GCC Makefile
now passes a --plugin option to ar if it supports one.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/526295

They are already collected via cmd/cgo.

The gccgo_link_c test is tweaked to do real linking as with this
change the cgo ldflags are not fully reflected in go build -n output,
since they now only come from the built archive.

This is a backport of https://go.dev/cl/497117 from the main repo.

For golang/go#60287

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/511675

In the Go 1.21 release the package internal/profile imports
internal/lazyregexp.  That works when bootstrapping with Go 1.17,
because that compiler has internal/lazyregep and permits importing it.
We also have internal/lazyregexp in libgo, but since it is not installed
it is not available for importing.  This CL adds internal/lazyregexp
to the list of internal packages that are installed for bootstrapping.

The Go 1.21, and earlier, releases have a couple of functions in
the internal/abi package that are always fully intrinsified.
The gofrontend recognizes and intrinsifies those functions as well.
However, the gofrontend was also building function descriptors
for references to the functions without calling them, which
failed because there was nothing to refer to.  That is OK for the
gc compiler, which guarantees that the functions are only called,
not referenced.  This CL arranges to not generate function descriptors
for these functions.

For golang/go#60913

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/504798

The final argument to mmap, of type off_t, varies.
In CL 445375 we changed it to always use the C off_t type,
but that broke 32-bit big-endian Linux systems.  On those systems,
using the C off_t type requires calling the mmap64 function.
In C this is automatically handled by the <sys/mman.h> file.
In Go, we would have to change the magic //extern comment to
call mmap64 when appropriate.  Rather than try to get that right,
we instead go through a C function that uses C implicit type
conversions to pick the right type.

Fixes PR go/110297

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/504415

In CL 384695 I simplified the code that built lists of benchmarks,
examples, and fuzz tests, and managed to break it. This CL corrects
the code to once again make the benchmarks available, and to run
the examples with output and the fuzz targets.

Doing this revealed a test failure in internal/fuzz on 32-bit x86:
a signalling NaN is turned into a quiet NaN on the 387 floating-point
stack that GCC uses by default. This CL skips the test.

Fixes golang/go#60826

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/503798

As of https://go.dev/cl/476695 golang.org/x/sys/unix can call
syscall.prlimit, so we need such a function in libgo.

For golang/go#46279
Fixes golang/go#59712

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/486576

Backport CL 421442 from upstream.

Original description:

Arrange for tests that call setMimeInit to fully restore the old values,
by clearing the sync.Once that controls initialization.

Once we've done that, call initMime in initMimeUnixTest because
otherwise the test types loaded there will be cleared by the call to
initMime that previously was not being done.

For golang/go#51648

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/483117

This directory should be changed upstream, not in the GCC repo.

Recently, mingw-w64 has got updated <msxml.h> from Wine which is included
indirectly by <windows.h> if `WIN32_LEAN_AND_MEAN` is not defined. The
`IXMLDOMDocument` class has a member function named `abort()`, which gets
affected by our `abort()` macro in "system.h".

`WIN32_LEAN_AND_MEAN` should, nevertheless, always be defined. This
can exclude 'APIs such as Cryptography, DDE, RPC, Shell, and Windows
Sockets' [1], and speed up compilation of these files a bit.

[1] https://learn.microsoft.com/en-us/windows/win32/winprog/using-the-windows-headers

gcc/

	PR middle-end/108300
	* config/xtensa/xtensa-dynconfig.c: Define `WIN32_LEAN_AND_MEAN`
	before <windows.h>.
	* diagnostic-color.cc: Likewise.
	* plugin.cc: Likewise.
	* prefix.cc: Likewise.

gcc/ada/

	PR middle-end/108300
	* adaint.c: Define `WIN32_LEAN_AND_MEAN` before `#include
	<windows.h>`.
	* cio.c: Likewise.
	* ctrl_c.c: Likewise.
	* expect.c: Likewise.
	* gsocket.h: Likewise.
	* mingw32.h: Likewise.
	* mkdir.c: Likewise.
	* rtfinal.c: Likewise.
	* rtinit.c: Likewise.
	* seh_init.c: Likewise.
	* sysdep.c: Likewise.
	* terminals.c: Likewise.
	* tracebak.c: Likewise.

gcc/jit/

	PR middle-end/108300
	* jit-w32.h: Define `WIN32_LEAN_AND_MEAN` before <windows.h>.

libatomic/

	PR middle-end/108300
	* config/mingw/lock.c: Define `WIN32_LEAN_AND_MEAN` before
	<windows.h>.

libffi/

	PR middle-end/108300
	* src/aarch64/ffi.c: Define `WIN32_LEAN_AND_MEAN` before
	<windows.h>.

libgcc/

	PR middle-end/108300
	* config/i386/enable-execute-stack-mingw32.c: Define
	`WIN32_LEAN_AND_MEAN` before <windows.h>.
	* libgcc2.c: Likewise.
	* unwind-generic.h: Likewise.

libgfortran/

	PR middle-end/108300
	* intrinsics/sleep.c: Define `WIN32_LEAN_AND_MEAN` before
	<windows.h>.

libgomp/

	PR middle-end/108300
	* config/mingw32/proc.c: Define `WIN32_LEAN_AND_MEAN` before
	<windows.h>.

libiberty/

	PR middle-end/108300
	* make-temp-file.c: Define `WIN32_LEAN_AND_MEAN` before <windows.h>.
	* pex-win32.c: Likewise.

libssp/

	PR middle-end/108300
	* ssp.c: Define `WIN32_LEAN_AND_MEAN` before <windows.h>.

libstdc++-v3/

	PR middle-end/108300
	* src/c++11/system_error.cc: Define `WIN32_LEAN_AND_MEAN` before
	<windows.h>.
	* src/c++11/thread.cc: Likewise.
	* src/c++17/fs_ops.cc: Likewise.
	* src/filesystem/ops.cc: Likewise.

libvtv/

	PR middle-end/108300
	* vtv_malloc.cc: Define `WIN32_LEAN_AND_MEAN` before <windows.h>.
	* vtv_rts.cc: Likewise.
	* vtv_utils.cc: Likewise.

Patch from Sören Tempel.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/458396

PR go/108057

The current version is the same as for the previous GCC release,
but there have been minor changes like new type descriptors that
make it impossible to run Go programs built with the previous GCC
release with the current libgo.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/456976

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/454275

This does the right thing for either glibc or musl on GNU/Linux.

Based on patch by Sören Tempel.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/454176

The last argument to the C mmap function is type off_t, not uintptr.
On some 32-bit systems, off_t is larger than uintptr.

Based on patch by Sören Tempel.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/445735

Previously, libgo relied on the _sigev_un implementation-specific
field in struct sigevent, which is only available on glibc.
This patch uses the sigev_notify_thread_id macro instead which is
mandated by timer_create(2). In theory, this should work with any libc
implementation for Linux. Unfortunately, there is an open glibc bug
as glibc does not define this macro. For this reason, a glibc-specific
workaround is required. Other libcs (such as musl) define the macro
and don't require the workaround.

See https://sourceware.org/bugzilla/show_bug.cgi?id=27417

This makes libgo compatible with musl libc.

Based on patch by Sören Tempel.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/434755

In GCCGO and gollvm, the logic for allocating one byte for the last field is:
1. the last field has zero size
2. the struct itself does not have zero size
3. the last field is not blank
this commit adds the last two conditions to runtime.structToFFI.

For golang/go#55146

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/431735

This ports https://go.dev/cl/421879 to libgo. This is a quick port to
update gofrontend to work with the version of cgo in gc mainline.
A more complete port will follow, changing the gc version of cmd/cgo to
choose an approach based on feature testing the gccgo in use.

Updates golang/go#46731

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/432338

We were ignoring all functions starting with "__morestack_", but not
the function "__morestack" itself.  Without this change, some tests
such as recover.go started failing recently, though I'm not sure
exactly what changed.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/427935

Musl defines SYS_timer_settime32, not SYS_timer_settime, on 32-bit systems.

Based on patch by Sören Tempel.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/420222

Avoid bash-specific ((expression)) syntax.  As the bash syntax
converts a non-zero value to a zero status (and a zero value to a 1
status), and POSIX arithmetic expansion does not, we have to negate
the result.

Based on patch by Sören Tempel.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/419154

Removing this doesn't change anything at least with glibc 2.33.
The include was added in https://go.dev/cl/6100049 but it's not
clear why.

Fixes PR go/106266

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/417294

Patches for musl support, from Sören Tempel.

Fixes PR go/105225

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/415294

Fixes golang/go#51850

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/414734

PR go/106033

Fixes golang/go#53469

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/413214

They are macros in musl libc, rather than typedefs, and -fgo-dump-spec
doesn't handle that case.

Based on patch by Sören Tempel.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/412075

Add blank lines after //sys comments where needed, and then run gofmt
on the syscall package with the new formatter.

This is the libgo version of CL 407136.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/412074

One of these days we will get this right.

Fixes PR go/105315

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/401374

Patch from Jonathan Wakely.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/401054