mirror of
https://github.com/golang/go
synced 2024-09-30 00:14:36 -06:00
abefcac10a
For most nodes (e.g., OPTRLIT, OMAKESLICE, OCONVIFACE), escape analysis prints "escapes to heap" or "does not escape" to indicate whether that node's allocation can be heap or stack allocated. These messages are also emitted for OADDR, even though OADDR does not actually allocate anything itself. Moreover, it's redundant because escape analysis already prints "moved to heap" diagnostics when an OADDR node like "&x" causes x to require heap allocation. Because OADDR nodes don't allocate memory, my escape analysis rewrite doesn't naturally emit the "escapes to heap" / "does not escape" diagnostics for them. It's also non-trivial to replicate the exact semantics esc.go uses for OADDR. Since there are so many of these messages, I'm disabling them in this CL by themselves. I modified esc.go to suppress the Warnl calls without any other behavior changes, and then used a shell script to automatically remove any ERROR messages mentioned by run.go in "missing error" or "no match for" lines. Fixes #16300. Updates #23109. Change-Id: I3993e2743c3ff83ccd0893f4e73b366ff8871a57 Reviewed-on: https://go-review.googlesource.com/c/go/+/170319 Run-TryBot: Matthew Dempsky <mdempsky@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Cherry Zhang <cherryyz@google.com> Reviewed-by: David Chase <drchase@google.com>
210 lines
7.9 KiB
Go
210 lines
7.9 KiB
Go
// errorcheck -0 -m -m -l
|
|
|
|
// 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.
|
|
|
|
// Note the doubled -m; this tests the "because" explanations for escapes,
|
|
// and is likely to be annoyingly fragile under compiler change.
|
|
// As long as the explanations look reasonably sane, meaning eyeball verify output of
|
|
// go build -gcflags '-l -m -m' escape_because.go
|
|
// and investigate changes, feel free to update with
|
|
// go run run.go -update_errors -- escape_because.go
|
|
|
|
package main
|
|
|
|
func main() {
|
|
}
|
|
|
|
var sink interface{}
|
|
|
|
type pair struct {
|
|
x, y *int
|
|
}
|
|
|
|
type Pairy interface {
|
|
EqualParts() bool
|
|
}
|
|
|
|
func (p *pair) EqualParts() bool { // ERROR "\(\*pair\).EqualParts p does not escape$"
|
|
return p != nil && (p.x == p.y || *p.x == *p.y)
|
|
}
|
|
|
|
func f1(p *int) { // ERROR "from \[3\]\*int literal \(array literal element\) at escape_because.go:34$" "from a \(assigned\) at escape_because.go:34$" "from a \(interface-converted\) at escape_because.go:35$" "from sink \(assigned to top level variable\) at escape_because.go:35$" "leaking param: p$"
|
|
a := [3]*int{p, nil, nil}
|
|
sink = a // ERROR "a escapes to heap$" "from sink \(assigned to top level variable\) at escape_because.go:35$"
|
|
|
|
}
|
|
|
|
func f2(q *int) { // ERROR "from &u \(address-of\) at escape_because.go:43$" "from &u \(interface-converted\) at escape_because.go:43$" "from pair literal \(struct literal element\) at escape_because.go:41$" "from s \(assigned\) at escape_because.go:40$" "from sink \(assigned to top level variable\) at escape_because.go:43$" "from t \(assigned\) at escape_because.go:41$" "from u \(assigned\) at escape_because.go:42$" "leaking param: q$"
|
|
s := q
|
|
t := pair{s, nil}
|
|
u := t // ERROR "moved to heap: u$"
|
|
sink = &u // ERROR "&u escapes to heap$" "from sink \(assigned to top level variable\) at escape_because.go:43$"
|
|
}
|
|
|
|
func f3(r *int) interface{} { // ERROR "from \[\]\*int literal \(slice-literal-element\) at escape_because.go:47$" "from c \(assigned\) at escape_because.go:47$" "from c \(interface-converted\) at escape_because.go:48$" "from ~r1 \(return\) at escape_because.go:48$" "leaking param: r"
|
|
c := []*int{r} // ERROR "\[\]\*int literal escapes to heap$" "from c \(assigned\) at escape_because.go:47$" "from c \(interface-converted\) at escape_because.go:48$" "from ~r1 \(return\) at escape_because.go:48$"
|
|
return c // "return" // ERROR "c escapes to heap$" "from ~r1 \(return\) at escape_because.go:48$"
|
|
}
|
|
|
|
func f4(a *int, s []*int) int { // ERROR "from \*s \(indirection\) at escape_because.go:51$" "from append\(s, a\) \(appended to slice\) at escape_because.go:52$" "from append\(s, a\) \(appendee slice\) at escape_because.go:52$" "leaking param content: s$" "leaking param: a$"
|
|
s = append(s, a)
|
|
return *(s[0])
|
|
}
|
|
|
|
func f5(s1, s2 []*int) int { // ERROR "from \*s1 \(indirection\) at escape_because.go:56$" "from \*s2 \(indirection\) at escape_because.go:56$" "from append\(s1, s2...\) \(appended slice...\) at escape_because.go:57$" "from append\(s1, s2...\) \(appendee slice\) at escape_because.go:57$" "leaking param content: s1$" "leaking param content: s2$"
|
|
s1 = append(s1, s2...)
|
|
return *(s1[0])
|
|
}
|
|
|
|
func f6(x, y *int) bool { // ERROR "f6 x does not escape$" "f6 y does not escape$"
|
|
p := pair{x, y}
|
|
var P Pairy = &p // ERROR "f6 &p does not escape$"
|
|
pp := P.(*pair)
|
|
return pp.EqualParts()
|
|
}
|
|
|
|
func f7(x map[int]*int, y int) *int { // ERROR "f7 x does not escape$"
|
|
z, ok := x[y]
|
|
if !ok {
|
|
return nil
|
|
}
|
|
return z
|
|
}
|
|
|
|
func f8(x int, y *int) *int { // ERROR "from ~r2 \(return\) at escape_because.go:78$" "from ~r2 \(returned from recursive function\) at escape_because.go:76$" "leaking param: y$" "moved to heap: x$"
|
|
if x <= 0 {
|
|
return y
|
|
}
|
|
x--
|
|
return f8(*y, &x)
|
|
}
|
|
|
|
func f9(x int, y ...*int) *int { // ERROR "from y\[0\] \(dot of pointer\) at escape_because.go:86$" "from ~r2 \(return\) at escape_because.go:86$" "from ~r2 \(returned from recursive function\) at escape_because.go:84$" "leaking param content: y$" "leaking param: y to result ~r2 level=1$" "moved to heap: x$"
|
|
if x <= 0 {
|
|
return y[0]
|
|
}
|
|
x--
|
|
return f9(*y[0], &x) // ERROR "f9 ... argument does not escape$"
|
|
}
|
|
|
|
func f10(x map[*int]*int, y, z *int) *int { // ERROR "f10 x does not escape$" "from x\[y\] \(key of map put\) at escape_because.go:93$" "from x\[y\] \(value of map put\) at escape_because.go:93$" "leaking param: y$" "leaking param: z$"
|
|
x[y] = z
|
|
return z
|
|
}
|
|
|
|
func f11(x map[*int]*int, y, z *int) map[*int]*int { // ERROR "f11 x does not escape$" "from map\[\*int\]\*int literal \(map literal key\) at escape_because.go:98$" "from map\[\*int\]\*int literal \(map literal value\) at escape_because.go:98$" "leaking param: y$" "leaking param: z$"
|
|
return map[*int]*int{y: z} // ERROR "from ~r3 \(return\) at escape_because.go:98$" "map\[\*int\]\*int literal escapes to heap$"
|
|
}
|
|
|
|
func f12() {
|
|
b := []byte("test") // ERROR "\(\[\]byte\)\(.test.\) escapes to heap$" "from b \(assigned\) at escape_because.go:102$" "from b \(passed to call\[argument escapes\]\) at escape_because.go:103$"
|
|
escape(b)
|
|
}
|
|
|
|
func escape(b []byte) { // ERROR "from panic\(b\) \(panic\) at escape_because.go:107$" "leaking param: b$"
|
|
panic(b)
|
|
}
|
|
|
|
func f13() {
|
|
b := []byte("test") // ERROR "\(\[\]byte\)\(.test.\) escapes to heap$" "from .out0 \(passed-to-and-returned-from-call\) at escape_because.go:112$" "from b \(assigned\) at escape_because.go:111$" "from c \(assigned\) at escape_because.go:112$" "from c \(passed to call\[argument escapes\]\) at escape_because.go:113$"
|
|
c := transmit(b)
|
|
escape(c)
|
|
}
|
|
|
|
func transmit(b []byte) []byte { // ERROR "from ~r1 \(return\) at escape_because.go:117$" "leaking param: b to result ~r1 level=0$"
|
|
return b
|
|
}
|
|
|
|
func f14() {
|
|
n := 32
|
|
s1 := make([]int, n) // ERROR "make\(\[\]int, n\) escapes to heap" "from make\(\[\]int, n\) \(non-constant size\)"
|
|
s2 := make([]int, 0, n) // ERROR "make\(\[\]int, 0, n\) escapes to heap" "from make\(\[\]int, 0, n\) \(non-constant size\)"
|
|
_, _ = s1, s2
|
|
}
|
|
|
|
func leakParams(p1, p2 *int) (*int, *int) { // ERROR "leaking param: p1 to result ~r2 level=0$" "from ~r2 \(return\) at escape_because.go:128$" "leaking param: p2 to result ~r3 level=0$" "from ~r3 \(return\) at escape_because.go:128$"
|
|
return p1, p2
|
|
}
|
|
|
|
func leakThroughOAS2() {
|
|
// See #26987.
|
|
i := 0 // ERROR "moved to heap: i$"
|
|
j := 0 // ERROR "moved to heap: j$"
|
|
sink, sink = &i, &j // ERROR "&i escapes to heap$" "from sink \(assign-pair\) at escape_because.go:135$" "&j escapes to heap$"
|
|
}
|
|
|
|
func leakThroughOAS2FUNC() {
|
|
// See #26987.
|
|
i := 0 // ERROR "moved to heap: i$"
|
|
j := 0
|
|
sink, _ = leakParams(&i, &j)
|
|
}
|
|
|
|
// The list below is all of the why-escapes messages seen building the escape analysis tests.
|
|
/*
|
|
for i in escape*go ; do echo compile $i; go build -gcflags '-l -m -m' $i >& `basename $i .go`.log ; done
|
|
grep 'from .* at ' escape*.log | sed -e 's/^.*(\([^()]*\))[^()]*$/\1/' | sort -u
|
|
*/
|
|
// sed RE above assumes that (reason) is the last parenthesized phrase in the line,
|
|
// and that none of the reasons contains any parentheses
|
|
|
|
/*
|
|
... arg to recursive call
|
|
address-of
|
|
appended slice...
|
|
appended to slice
|
|
appendee slice
|
|
arg to ...
|
|
arg to recursive call
|
|
array-element-equals
|
|
array literal element
|
|
assigned
|
|
assigned to top level variable
|
|
assign-pair-dot-type
|
|
assign-pair-func-call
|
|
captured by a closure
|
|
captured by called closure
|
|
dot
|
|
dot-equals
|
|
dot of pointer
|
|
fixed-array-index-of
|
|
go func arg
|
|
indirection
|
|
interface-converted
|
|
key of map put
|
|
map literal key
|
|
map literal value
|
|
non-constant size
|
|
panic
|
|
parameter to indirect call
|
|
passed-to-and-returned-from-call
|
|
passed to call[argument content escapes]
|
|
passed to call[argument escapes]
|
|
pointer literal
|
|
range-deref
|
|
receiver in indirect call
|
|
return
|
|
returned from recursive function
|
|
slice-element-equals
|
|
slice-literal-element
|
|
star-dot-equals
|
|
star-equals
|
|
struct literal element
|
|
too large for stack
|
|
value of map put
|
|
*/
|
|
|
|
// Expected, but not yet seen (they may be unreachable):
|
|
|
|
/*
|
|
append-first-arg
|
|
assign-pair-mapr
|
|
assign-pair-receive
|
|
call receiver
|
|
map index
|
|
pointer literal [assign]
|
|
slice literal element
|
|
*/
|