defer func() {
		if err := b.Close(); err != nil {
			base.Fatal(err)
		}
	}()

	cppflags, cflags, cxxflags, fflags, ldflags, err := b.CFlags(&load.Package{})
	if err != nil {
		// Should not happen - b.CFlags was given an empty package.
		fmt.Fprintf(os.Stderr, "go: invalid cflags: %v\n", err)
		return nil
	}
	cmd := b.GccCmd(".", "")

	join := func(s []string) string {

}

type itimerval struct {
	it_interval timeval
	it_value    timeval
}

type umtx_time struct {
	_timeout timespec
	_flags   uint32
	_clockid uint32
}

type keventt struct {
	ident  uint64
	filter int16
	flags  uint16
	fflags uint32
	data   int64
	udata  *byte
	ext    [4]uint64
}

type bintime struct {
	sec  int64
	frac uint64
}

	}
	return args
}

// CFlags returns the flags to use when invoking the C, C++ or Fortran compilers, or cgo.
func (b *Builder) CFlags(p *load.Package) (cppflags, cflags, cxxflags, fflags, ldflags []string, err error) {
	if cppflags, err = buildFlags("CPPFLAGS", "", p.CgoCPPFLAGS, checkCompilerFlags); err != nil {
		return
	}
	if cflags, err = buildFlags("CFLAGS", DefaultCFlags, p.CgoCFLAGS, checkCompilerFlags); err != nil {

		extraLDFlags := ""
		if strings.Contains(testenv.Builder(), "clang") {
			extraLDFlags += " -fuse-ld=lld"
		}
		const cflags = "-flto -Wno-lto-type-mismatch -Wno-unknown-warning-option"
		cmd.Env = append(cmd.Environ(),
			"CGO_CFLAGS="+cflags,
			"CGO_CXXFLAGS="+cflags,
			"CGO_LDFLAGS="+cflags+extraLDFlags)
	}
	out, err := cmd.CombinedOutput()
	if string(out) != "OK\n" {
		t.Errorf("%s", string(out))
	}

[!GOOS:darwin] skip
[!cgo] skip

! go build
stderr 'invalid flag in #cgo LDFLAGS: -lto_library'

-- go.mod --
module ldflag

-- main.go --
package main

// #cgo CFLAGS: -flto
// #cgo LDFLAGS: -lto_library bad.dylib
import "C"

[!GOOS:linux] skip
[!compiler:gc] skip
[!cgo] skip
[!GOARCH:ppc64le] skip

go build -ldflags='-linkmode=internal'
exec ./abitest
stdout success

go build -buildmode=pie -o abitest.pie -ldflags='-linkmode=internal'
exec ./abitest.pie
stdout success

-- go.mod --
module abitest

-- abitest.go --
package main

/*
#cgo CFLAGS: -Os

int foo_fpr() {
        asm volatile("":::"fr31","fr30","fr29","fr28");
}

ALL_OSVERSIONS.windows := 1809 ltsc2022
ALL_OS_ARCH.windows = $(foreach arch, $(ALL_ARCH.windows), $(foreach osversion, ${ALL_OSVERSIONS.windows}, windows-$(arch)-${osversion}))
ALL_OS_ARCH = $(foreach os, $(ALL_OS), ${ALL_OS_ARCH.${os}})

CFLAGS = -Os -Wall -Werror -static -DVERSION=v$(TAG)-$(REV)
KUBE_CROSS_IMAGE ?= registry.k8s.io/build-image/kube-cross
KUBE_CROSS_VERSION ?= $(shell cat ../build-image/cross/VERSION)

// license that can be found in the LICENSE file.

/*
Package flag implements command-line flag parsing.

# Usage

Define flags using [flag.String], [Bool], [Int], etc.

This declares an integer flag, -n, stored in the pointer nFlag, with type *int:

	import "flag"
	var nFlag = flag.Int("n", 1234, "help message for flag n")

If you like, you can bind the flag to a variable using the Var() functions.

	var flagvar int

	// for the whole fd lifetime. The notifications are automatically unregistered
	// when fd is closed.
	var ev [2]keventt
	*(*uintptr)(unsafe.Pointer(&ev[0].ident)) = fd
	ev[0].filter = _EVFILT_READ
	ev[0].flags = _EV_ADD | _EV_CLEAR
	ev[0].fflags = 0
	ev[0].data = 0

	if goarch.PtrSize == 4 {
		// We only have a pointer-sized field to store into,
		// so on a 32-bit system we get no sequence protection.

	if path == "" {
		return -1, EINVAL
	}
	dirFd, pathPtr, pathLen := preparePath(path)

	var oflags oflags
	if (openmode & O_CREATE) != 0 {
		oflags |= OFLAG_CREATE
	}
	if (openmode & O_TRUNC) != 0 {
		oflags |= OFLAG_TRUNC
	}
	if (openmode & O_EXCL) != 0 {
		oflags |= OFLAG_EXCL
	}

	var rights rights
	switch openmode & (O_RDONLY | O_WRONLY | O_RDWR) {
	case O_RDONLY: