import/path: issue title

[intchar-hub]

Go version

go version go1.23.8 darwin/arm64

Output of go env in your module/workspace:

GO111MODULE='on'
GOARCH='arm64'
GOBIN=''
GOCACHE='/Users/bytedance/Library/Caches/go-build'
GOENV='/Users/bytedance/Library/Application Support/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFLAGS=''
GOHOSTARCH='arm64'
GOHOSTOS='darwin'
GOINSECURE=''
GOMODCACHE='/Users/bytedance/go/pkg/mod'
GONOPROXY='*.byted.org,*.everphoto.cn,git.smartisan.com'
GONOSUMDB='*.byted.org,*.everphoto.cn,git.smartisan.com'
GOOS='darwin'
GOPATH='/Users/bytedance/go'
GOPRIVATE='*.byted.org,*.everphoto.cn,git.smartisan.com'
GOPROXY='https://goproxy.byted.org|https://goproxy.cn|direct'
GOROOT='/Users/bytedance/go/pkg/mod/golang.org/toolchain@v0.0.1-go1.23.8.darwin-arm64'
GOSUMDB='sum.golang.google.cn'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/Users/bytedance/go/pkg/mod/golang.org/toolchain@v0.0.1-go1.23.8.darwin-arm64/pkg/tool/darwin_arm64'
GOVCS=''
GOVERSION='go1.23.8'
GODEBUG=''
GOTELEMETRY='local'
GOTELEMETRYDIR='/Users/bytedance/Library/Application Support/go/telemetry'
GCCGO='gccgo'
GOARM64='v8.0'
AR='ar'
CC='clang'
CXX='clang++'
CGO_ENABLED='1'
GOMOD='/dev/null'
GOWORK=''
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
PKG_CONFIG='pkg-config'

What did you do?

package main

type Person struct {
	Name      string
	Age       int
	TestSlice []string
}

// main demo5 - 测试 marshal 和 unmarshal 方法对 nil 值的实践
func main() {
	pList1 := []Person{
		{
			Name: "1",
		},
		{
			Name: "2",
		},
	}
	pList2 := []Person{
		{
			Name: "3",
		},
		{
			Name: "4",
		},
	}
	println("1111", &pList1, &pList2, &pList1[0])
	test(pList1, pList2)
	println("1111", &pList1, &pList2, &pList1[0])
}

func test(personList ...[]Person) {
	println(&personList[0], &personList[1], &personList[0][0])
	for _, persons := range personList {
		for i := range persons {
			persons[i].Name = "test"
		}
	}
	testPerson := []Person{
		{
			Name: "5",
		},
	}
	println("2222", &testPerson)
	personList[0] = testPerson
}

What did you see happen?

1111 0x14000050628 0x14000050610 0x14000050640
0x140000506a8 0x140000506c0 0x14000050640
2222 0x1400009cdf8
1111 0x1400009ce28 0x1400009ce10 0x1400009ce40

What did you expect to see?

After calling the test function, the addresses of pList1 and pList2 do not change.
However, if the following lines:

println(&personList[0], &personList[1], &personList[0][0])
println("2222", &testPerson)

are omitted, the addresses of pList1 and pList2 are the same.

[randall77]

What makes you think the addresses won't change?

We do stack copying, so if plist1 and plist2 are on the stack, their addresses will change.

[gabyhelp]

Related Issues

• bug: look like to watch same address when assign to another variable from sub-slice. #56617 (closed)
• go/compile: new variable is not assigned a new address? #44954 (closed)
• container/list: the last Element is changed when use array append #31404 (closed)
• Slice has unpredictable result #68010 (closed)
• import/path: issue title #69161 (closed)
• It is a GC issue? #44317 (closed)
• Convert slice of type A to slice of pointers to type A #22791 (closed)
• affected/package: builtin and os #63672 (closed)
• making a copy of struct and taking address of it returns pointer to the same struct #59341 (closed)

Related Discussions

• Unexpected behavior with array of pointers to structs vs array of structs

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