1 // Copyright 2012 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 main 6 7 import ( 8 "fmt" 9 "os" 10 "strings" 11 ) 12 13 /* 14 * Helpers for building runtime. 15 */ 16 17 // mkzversion writes zversion.go: 18 // 19 // package runtime 20 // const defaultGoroot = <goroot> 21 // const theVersion = <version> 22 // const goexperiment = <goexperiment> 23 // const stackGuardMultiplier = <multiplier value> 24 // const buildVersion = <build version> 25 // 26 func mkzversion(dir, file string) { 27 out := fmt.Sprintf( 28 "// auto generated by go tool dist\n"+ 29 "\n"+ 30 "package runtime\n"+ 31 "\n"+ 32 "const defaultGoroot = `%s`\n"+ 33 "const theVersion = `%s`\n"+ 34 "const goexperiment = `%s`\n"+ 35 "const stackGuardMultiplier = %d\n"+ 36 "var buildVersion = theVersion\n", goroot_final, findgoversion(), os.Getenv("GOEXPERIMENT"), stackGuardMultiplier()) 37 38 writefile(out, file, writeSkipSame) 39 } 40 41 // mkzbootstrap writes cmd/internal/obj/zbootstrap.go: 42 // 43 // package obj 44 // 45 // const defaultGOROOT = <goroot> 46 // const defaultGO386 = <go386> 47 // const defaultGOARM = <goarm> 48 // const defaultGOOS = runtime.GOOS 49 // const defaultGOARCH = runtime.GOARCH 50 // const defaultGO_EXTLINK_ENABLED = <goextlinkenabled> 51 // const version = <version> 52 // const stackGuardMultiplier = <multiplier value> 53 // const goexperiment = <goexperiment> 54 // 55 // The use of runtime.GOOS and runtime.GOARCH makes sure that 56 // a cross-compiled compiler expects to compile for its own target 57 // system. That is, if on a Mac you do: 58 // 59 // GOOS=linux GOARCH=ppc64 go build cmd/compile 60 // 61 // the resulting compiler will default to generating linux/ppc64 object files. 62 // This is more useful than having it default to generating objects for the 63 // original target (in this example, a Mac). 64 func mkzbootstrap(file string) { 65 out := fmt.Sprintf( 66 "// auto generated by go tool dist\n"+ 67 "\n"+ 68 "package obj\n"+ 69 "\n"+ 70 "import \"runtime\"\n"+ 71 "\n"+ 72 "const defaultGOROOT = `%s`\n"+ 73 "const defaultGO386 = `%s`\n"+ 74 "const defaultGOARM = `%s`\n"+ 75 "const defaultGOOS = runtime.GOOS\n"+ 76 "const defaultGOARCH = runtime.GOARCH\n"+ 77 "const defaultGO_EXTLINK_ENABLED = `%s`\n"+ 78 "const version = `%s`\n"+ 79 "const stackGuardMultiplier = %d\n"+ 80 "const goexperiment = `%s`\n", 81 goroot_final, go386, goarm, goextlinkenabled, findgoversion(), stackGuardMultiplier(), os.Getenv("GOEXPERIMENT")) 82 83 writefile(out, file, writeSkipSame) 84 } 85 86 // stackGuardMultiplier returns a multiplier to apply to the default 87 // stack guard size. Larger multipliers are used for non-optimized 88 // builds that have larger stack frames. 89 func stackGuardMultiplier() int { 90 for _, s := range strings.Split(os.Getenv("GO_GCFLAGS"), " ") { 91 if s == "-N" { 92 return 2 93 } 94 } 95 return 1 96 } 97
