}
	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 {

}

func TestToleratesOptimizationFlag(t *testing.T) {
	for _, cflags := range []string{
		"",
		"-O",
	} {
		cflags := cflags
		t.Run(cflags, func(t *testing.T) {
			testenv.MustHaveGoBuild(t)
			testenv.MustHaveCGO(t)
			t.Parallel()

			cmd := exec.Command("go", "build", path("issue14669.go"))
			cmd.Env = append(os.Environ(), "CGO_CFLAGS="+cflags)
			out, err := cmd.CombinedOutput()
			if err != nil {

		t.Logf("%s %v -c -o %s %s", cc, cflags, obj, csrcFile)
		if out, err := testenv.Command(t, cc, append(cflags, "-c", "-o", obj, csrcFile)...).CombinedOutput(); err != nil {
			t.Logf("%s", out)
			t.Fatal(err)
		}
	}

	sysoObj := filepath.Join(dir, "ldr.syso")
	t.Logf("%s %v -nostdlib -r -o %s %v", cc, cflags, sysoObj, objs)

			c.cFlags = append(c.cFlags, "-fPIC")
			c.ldFlags = append(c.ldFlags, "-fPIC", "-static-libtsan")
		}

	case "address":
		c.goFlags = append(c.goFlags, "-asan")
		// Set the debug mode to print the C stack trace.
		c.cFlags = append(c.cFlags, "-g")

	case "fuzzer":
		c.goFlags = append(c.goFlags, "-tags=libfuzzer", "-gcflags=-d=libfuzzer")

	default:

	"cmd/internal/quoted"
)

var goflags []string // cached $GOFLAGS list; can be -x or --x form

// GOFLAGS returns the flags from $GOFLAGS.
// The list can be assumed to contain one string per flag,
// with each string either beginning with -name or --name.
func GOFLAGS() []string {
	InitGOFLAGS()
	return goflags
}

// InitGOFLAGS initializes the goflags list from $GOFLAGS.

	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 {

) >_const.go

# Pull out the error names for later.
errors=$(
	echo '#include <errno.h>' | $CC -x c - -E -dM $ccflags |
	awk '$1=="#define" && $2 ~ /^E[A-Z0-9_]+$/ { print $2 }' |
	sort
)

# Pull out the signal names for later.
signals=$(
	echo '#include <signal.h>' | $CC -x c - -E -dM $ccflags |
	awk '$1=="#define" && $2 ~ /^SIG[A-Z0-9]+$/ { print $2 }' |
	grep -v 'SIGSTKSIZE\|SIGSTKSZ\|SIGRT\|SIGMAX64' |
	sort

[short] skip # rebuilds all of std

# Set up fresh GOCACHE.
env GOCACHE=$WORK/gocache
mkdir $GOCACHE

# Verify the standard library (specifically internal/runtime/atomic) can be
# built with -gcflags when -n is given. See golang.org/issue/29346.
go build -n -gcflags=all='-l' std

		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))
	}

// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Package flags implements top-level flags and the usage message for the assembler.
package flags

import (
	"cmd/internal/obj"
	"cmd/internal/objabi"
	"flag"
	"fmt"
	"os"
	"path/filepath"
	"strings"
)

var (