1 // Copyright 2021 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 package runtime_test 6 7 import ( 8 "testing" 9 ) 10 11 func TestIssue48807(t *testing.T) { 12 for _, i := range []uint64{ 13 0x8234508000000001, // from issue48807 14 1<<56 + 1<<32 + 1, 15 } { 16 got := float32(i) 17 dontwant := float32(float64(i)) 18 if got == dontwant { 19 // The test cases above should be uint64s such that 20 // this equality doesn't hold. These examples trigger 21 // the case where using an intermediate float64 doesn't work. 22 t.Errorf("direct float32 conversion doesn't work: arg=%x got=%x dontwant=%x", i, got, dontwant) 23 } 24 } 25 } 26