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// errorcheck
// Check flagging of invalid conversion of constant to float32/float64 near min/max boundaries.
// Copyright 2014 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.
package main
// See float_lit2.go for motivation for these values.
const (
two24 = 1.0 * (1 << 24)
two53 = 1.0 * (1 << 53)
two64 = 1.0 * (1 << 64)
two128 = two64 * two64
two256 = two128 * two128
two512 = two256 * two256
two768 = two512 * two256
two1024 = two512 * two512
ulp32 = two128 / two24
max32 = two128 - ulp32
ulp64 = two1024 / two53
max64 = two1024 - ulp64
)
var x = []interface{}{
float32(max32 + ulp32/2 - 1), // ok
float32(max32 + ulp32/2 - two128/two256), // ok
float32(max32 + ulp32/2), // ERROR "constant 3\.40282e\+38 overflows float32|cannot convert.*to type float32"
float32(-max32 - ulp32/2 + 1), // ok
float32(-max32 - ulp32/2 + two128/two256), // ok
float32(-max32 - ulp32/2), // ERROR "constant -3\.40282e\+38 overflows float32|cannot convert.*to type float32"
// If the compiler's internal floating point representation
// is shorter than 1024 bits, it cannot distinguish max64+ulp64/2-1 and max64+ulp64/2.
float64(max64 + ulp64/2 - two1024/two256), // ok
float64(max64 + ulp64/2 - 1), // ok
float64(max64 + ulp64/2), // ERROR "constant 1\.79769e\+308 overflows float64|cannot convert.*to type float64"
float64(-max64 - ulp64/2 + two1024/two256), // ok
float64(-max64 - ulp64/2 + 1), // ok
float64(-max64 - ulp64/2), // ERROR "constant -1\.79769e\+308 overflows float64|cannot convert.*to type float64"
}
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