// Otherwise Switch prints all the errors using base.Error.
//
// See https://go.dev/doc/toolchain#switch.
type Switcher struct {
	TooNew *gover.TooNewError // max go requirement observed
	Errors []error            // errors collected so far
}

// Error reports the error to the Switcher,
// which saves it for processing during Switch.
func (s *Switcher) Error(err error) {

	mcall(coroswitch_m)
}

//go:linkname coroswitch

// coroswitch switches to the goroutine blocked on c
// and then blocks the current goroutine on c.
func coroswitch(c *coro) {
	gp := getg()
	gp.coroarg = c
	mcall(coroswitch_m)
}

// coroswitch_m is the implementation of coroswitch
// that runs on the m stack.
//
// Note: Coroutine switches are expected to happen at
// an order of magnitude (or more) higher frequency

// is implementing (Inter), and some ancillary information.
//
// allocated in non-garbage-collected memory
type ITab struct {
	Inter *InterfaceType
	Type  *Type
	Hash  uint32     // copy of Type.Hash. Used for type switches.
	Fun   [1]uintptr // variable sized. fun[0]==0 means Type does not implement Inter.
}

// EmptyInterface describes the layout of a "interface{}" or a "any."

	// already running on CPU and there can be lots of them, so a woken up
	// waiter has good chances of losing. In such case it is queued at front
	// of the wait queue. If a waiter fails to acquire the mutex for more than 1ms,
	// it switches mutex to the starvation mode.
	//
	// In starvation mode ownership of the mutex is directly handed off from
	// the unlocking goroutine to the waiter at the front of the queue.

// Copyright 2023 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.

// Tests coroutine switches.

//go:build ignore

package main

import (
	"iter"
	"log"
	"os"
	"runtime/trace"
	"sync"
)

func main() {
	// Start tracing.
	if err := trace.Start(os.Stdout); err != nil {
		log.Fatalf("failed to start tracing: %v", err)
	}

== Choosing a log level

You can choose different log levels from the command line switches shown in <<#logLevelCommandLineOptions, Log level command-line options>>.

You can also configure the log level using <<build_environment.adoc#sec:gradle_configuration_properties,`gradle.properties`>>.

In <<#stacktraces,Stacktrace command-line options>> you can find the command line switches which affect stacktrace logging.

[[logLevelCommandLineOptions]]

	} else if b.gccSupportsFlag(compiler, "-fdebug-prefix-map=a=b") {
		defs = append(defs, "-fdebug-prefix-map="+b.WorkDir+"=/tmp/go-build")
	}
	if b.gccSupportsFlag(compiler, "-gno-record-gcc-switches") {
		defs = append(defs, "-gno-record-gcc-switches")
	}
	return b.Shell(a).run(p.Dir, p.ImportPath, nil, compiler, "-Wall", "-g",
		"-I", a.Objdir, "-I", inc, "-o", ofile, defs, "-c", cfile)
}

	m.Inter = inter
	m.Type = typ
	// The hash is used in type switches. However, compiler statically generates itab's
	// for all interface/type pairs used in switches (which are added to itabTable
	// in itabsinit). The dynamically-generated itab's never participate in type switches,
	// and thus the hash is irrelevant.
	// Note: m.Hash is _not_ the hash used for the runtime itabTable hash table.

//
// runtime.cgocall (below) calls entersyscall so as not to block
// other goroutines or the garbage collector, and then calls
// runtime.asmcgocall(_cgo_Cfunc_f, frame).
//
// runtime.asmcgocall (in asm_$GOARCH.s) switches to the m->g0 stack
// (assumed to be an operating system-allocated stack, so safe to run
// gcc-compiled code on) and calls _cgo_Cfunc_f(frame).
//
// _cgo_Cfunc_f invokes the actual C function f with arguments

If a developer continuously changes a single file, there is likely no need to rebuild all the other files in the project.

However, what happens when the same developer switches to a new branch created last week?
The files are rebuilt, even though the developer is building something that has been built before.

This is where a *build cache* is helpful.