github.com/mdempsky/go@v0.0.0-20151201204031-5dd372bd1e70/test/escape4.go (about)

     1  // errorcheck -0 -m
     2  
     3  // Copyright 2010 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  // Test, using compiler diagnostic flags, that the escape analysis is working.
     8  // Compiles but does not run.  Inlining is enabled.
     9  
    10  package foo
    11  
    12  var p *int
    13  
    14  func alloc(x int) *int { // ERROR "can inline alloc" "moved to heap: x"
    15  	return &x // ERROR "&x escapes to heap"
    16  }
    17  
    18  var f func()
    19  
    20  func f1() {
    21  	p = alloc(2) // ERROR "inlining call to alloc" "&x escapes to heap" "moved to heap: x"
    22  
    23  	// Escape analysis used to miss inlined code in closures.
    24  
    25  	func() { // ERROR "func literal does not escape" "can inline f1.func1"
    26  		p = alloc(3) // ERROR "inlining call to alloc" "&x escapes to heap" "moved to heap: x"
    27  	}()
    28  
    29  	f = func() { // ERROR "func literal escapes to heap" "can inline f1.func2"
    30  		p = alloc(3) // ERROR "inlining call to alloc" "&x escapes to heap" "moved to heap: x"
    31  	}
    32  	f()
    33  }
    34  
    35  func f2() {} // ERROR "can inline f2"
    36  
    37  // No inline for panic, recover.
    38  func f3() { panic(1) }
    39  func f4() { recover() }
    40  
    41  func f5() *byte {
    42  	type T struct {
    43  		x [1]byte
    44  	}
    45  	t := new(T)    // ERROR "new.T. escapes to heap"
    46  	return &t.x[0] // ERROR "&t.x.0. escapes to heap"
    47  }
    48  
    49  func f6() *byte {
    50  	type T struct {
    51  		x struct {
    52  			y byte
    53  		}
    54  	}
    55  	t := new(T)   // ERROR "new.T. escapes to heap"
    56  	return &t.x.y // ERROR "&t.x.y escapes to heap"
    57  }