modernc.org/gc@v1.0.1-0.20240304020402-f0dba7c97c2b/testdata/errchk/test/fixedbugs/issue20250.go (about)

     1  // errorcheck -0 -live -l -d=compilelater,eagerwb
     2  
     3  // Copyright 2017 The Go Authors. All rights reserved.
     4  // Use of this source code is governed by a BSD-style
     5  // license that can be found in the LICENSE file.
     6  
     7  // Issue 20250: liveness differed with concurrent compilation
     8  // due to propagation of addrtaken to outer variables for
     9  // closure variables.
    10  
    11  // TODO(austin): This expects function calls to the write barrier, so
    12  // we enable the legacy eager write barrier. Fix this once the
    13  // buffered write barrier works on all arches.
    14  
    15  package p
    16  
    17  type T struct {
    18  	s string
    19  }
    20  
    21  func f(a T) { // ERROR "live at entry to f: a"
    22  	var e interface{}
    23  	func() { // ERROR "live at entry to f.func1: a &e"
    24  		e = a.s // ERROR "live at call to convT2Estring: a &e" "live at call to writebarrierptr: a"
    25  	}() // ERROR "live at call to f.func1: e$"
    26  	// Before the fix, both a and e were live at the previous line.
    27  	_ = e
    28  }