staticcheck: cgo: SA4000 false positive on generated 0 == 0

[sergefdrv]

This code

package pkg

// void foo(void **p) {}
import "C"
import "unsafe"

func Foo() {
	var p unsafe.Pointer

	C.foo(&p)
}

gives a false positive error identical expressions on the left and right side of the '==' operator (SA4000) pointing beyond the end of the line C.foo(&p).

The reason is that cgo generates the following Go code

// Code generated by cmd/cgo; DO NOT EDIT.

//line test.go:1:1
package pkg

// void foo(void **p) {}
import _ "unsafe"
import "unsafe"

func Foo() {
	var p unsafe.Pointer

	func() { _cgoBase0 := /*line :10:8*/&p; _cgo0 := _cgoBase0; _cgoCheckPointer(_cgoBase0, 0 == 0); _Cfunc_foo(_cgo0); }()
}

So staticcheck actually complains on 0 == 0 expression generated by cgo.

[sergefdrv]

I was thinking for a moment that this can be a fault of cgo generating the offending code. But it might actually be a bit more complicated.

[ainar-g]

When will the evils of shadowing end?

[dominikh]

When will the evils of shadowing end?

Part of me wishes for a way to refer to outer scopes, and the universe scope, explicitly. But I worry that would only make things worse :-)

[ainar-g]

@dominikh You can kind–of–sort–of do that. See my comment on the Go issue tracker. Stinky, but works.

[sergefdrv]

@dominikh Thanks!