From 8b2feaee81d7a16adc59e61d06c1e7314d3a5408 Mon Sep 17 00:00:00 2001 From: Matt Madison Date: Mon, 19 Feb 2018 08:50:59 -0800 Subject: [PATCH 2/9] cmd/go: make content-based hash generation less pedantic Go 1.10's build tool now uses content-based hashes to determine when something should be built or re-built. This same mechanism is used to maintain a built-artifact cache for speeding up builds. However, the hashes it generates include information that doesn't work well with OE, nor with using a shared runtime library. First, it embeds path names to source files, unless building within GOROOT. This prevents the building of a package in GOPATH for later staging into GOROOT. This patch adds support for the environment variable GOPATH_OMIT_IN_ACTIONID. If present, path name embedding is disabled. Second, if cgo is enabled, the build ID for cgo-related packages will include the current value of the environment variables for invoking the compiler (CC, CXX, FC) and any CGO_xxFLAGS variables. Only if the settings used during a compilation exactly match, character for character, the values used for compiling runtime/cgo or any other cgo-enabled package being imported, will the tool decide that the imported package is up-to-date. This is done to help ensure correctness, but is overly simplistic and effectively prevents the reuse of built artifacts that use cgo (or shared runtime, which includes runtime/cgo). This patch filters out all compiler flags except those beginning with '-m'. The default behavior can be restored by setting the CGO_PEDANTIC environment variable. Upstream-Status: Inappropriate [OE specific] Signed-off-by: Matt Madison --- src/cmd/go/internal/envcmd/env.go | 2 +- src/cmd/go/internal/work/exec.go | 63 ++++++++++++++++++++++++++++----------- 2 files changed, 46 insertions(+), 19 deletions(-) diff --git a/src/cmd/go/internal/envcmd/env.go b/src/cmd/go/internal/envcmd/env.go index f891123f9c..ebacfbfdbc 100644 --- a/src/cmd/go/internal/envcmd/env.go +++ b/src/cmd/go/internal/envcmd/env.go @@ -113,7 +113,7 @@ func findEnv(env []cfg.EnvVar, name string) string { func ExtraEnvVars() []cfg.EnvVar { var b work.Builder b.Init() - cppflags, cflags, cxxflags, fflags, ldflags, err := b.CFlags(&load.Package{}) + cppflags, cflags, cxxflags, fflags, ldflags, err := b.CFlags(&load.Package{}, false) if err != nil { // Should not happen - b.CFlags was given an empty package. fmt.Fprintf(os.Stderr, "go: invalid cflags: %v\n", err) diff --git a/src/cmd/go/internal/work/exec.go b/src/cmd/go/internal/work/exec.go index c4c1500eb2..b0f6b45647 100644 --- a/src/cmd/go/internal/work/exec.go +++ b/src/cmd/go/internal/work/exec.go @@ -173,6 +173,8 @@ func (b *Builder) Do(root *Action) { wg.Wait() } +var omitGopath = os.Getenv("GOPATH_OMIT_IN_ACTIONID") != "" + // buildActionID computes the action ID for a build action. func (b *Builder) buildActionID(a *Action) cache.ActionID { p := a.Package @@ -189,7 +191,7 @@ func (b *Builder) buildActionID(a *Action) cache.ActionID { // but it does not hide the exact value of $GOPATH. // Include the full dir in that case. // Assume b.WorkDir is being trimmed properly. - if !p.Goroot && !strings.HasPrefix(p.Dir, b.WorkDir) { + if !p.Goroot && !omitGopath && !strings.HasPrefix(p.Dir, b.WorkDir) { fmt.Fprintf(h, "dir %s\n", p.Dir) } fmt.Fprintf(h, "goos %s goarch %s\n", cfg.Goos, cfg.Goarch) @@ -197,13 +199,13 @@ func (b *Builder) buildActionID(a *Action) cache.ActionID { fmt.Fprintf(h, "omitdebug %v standard %v local %v prefix %q\n", p.Internal.OmitDebug, p.Standard, p.Internal.Local, p.Internal.LocalPrefix) if len(p.CgoFiles)+len(p.SwigFiles) > 0 { fmt.Fprintf(h, "cgo %q\n", b.toolID("cgo")) - cppflags, cflags, cxxflags, fflags, _, _ := b.CFlags(p) - fmt.Fprintf(h, "CC=%q %q %q\n", b.ccExe(), cppflags, cflags) + cppflags, cflags, cxxflags, fflags, _, _ := b.CFlags(p, true) + fmt.Fprintf(h, "CC=%q %q %q\n", b.ccExe(true), cppflags, cflags) if len(p.CXXFiles)+len(p.SwigFiles) > 0 { - fmt.Fprintf(h, "CXX=%q %q\n", b.cxxExe(), cxxflags) + fmt.Fprintf(h, "CXX=%q %q\n", b.cxxExe(true), cxxflags) } if len(p.FFiles) > 0 { - fmt.Fprintf(h, "FC=%q %q\n", b.fcExe(), fflags) + fmt.Fprintf(h, "FC=%q %q\n", b.fcExe(true), fflags) } // TODO(rsc): Should we include the SWIG version or Fortran/GCC/G++/Objective-C compiler versions? } @@ -1731,33 +1733,33 @@ var ( // gccCmd returns a gcc command line prefix // defaultCC is defined in zdefaultcc.go, written by cmd/dist. func (b *Builder) GccCmd(incdir, workdir string) []string { - return b.compilerCmd(b.ccExe(), incdir, workdir) + return b.compilerCmd(b.ccExe(false), incdir, workdir) } // gxxCmd returns a g++ command line prefix // defaultCXX is defined in zdefaultcc.go, written by cmd/dist. func (b *Builder) GxxCmd(incdir, workdir string) []string { - return b.compilerCmd(b.cxxExe(), incdir, workdir) + return b.compilerCmd(b.cxxExe(false), incdir, workdir) } // gfortranCmd returns a gfortran command line prefix. func (b *Builder) gfortranCmd(incdir, workdir string) []string { - return b.compilerCmd(b.fcExe(), incdir, workdir) + return b.compilerCmd(b.fcExe(false), incdir, workdir) } // ccExe returns the CC compiler setting without all the extra flags we add implicitly. -func (b *Builder) ccExe() []string { - return b.compilerExe(origCC, cfg.DefaultCC(cfg.Goos, cfg.Goarch)) +func (b *Builder) ccExe(filtered bool) []string { + return b.compilerExe(origCC, cfg.DefaultCC(cfg.Goos, cfg.Goarch), filtered) } // cxxExe returns the CXX compiler setting without all the extra flags we add implicitly. -func (b *Builder) cxxExe() []string { - return b.compilerExe(origCXX, cfg.DefaultCXX(cfg.Goos, cfg.Goarch)) +func (b *Builder) cxxExe(filtered bool) []string { + return b.compilerExe(origCXX, cfg.DefaultCXX(cfg.Goos, cfg.Goarch), filtered) } // fcExe returns the FC compiler setting without all the extra flags we add implicitly. -func (b *Builder) fcExe() []string { - return b.compilerExe(os.Getenv("FC"), "gfortran") +func (b *Builder) fcExe(filtered bool) []string { + return b.compilerExe(os.Getenv("FC"), "gfortran", filtered) } // compilerExe returns the compiler to use given an @@ -1766,11 +1768,14 @@ func (b *Builder) fcExe() []string { // of the compiler but can have additional arguments if they // were present in the environment value. // For example if CC="gcc -DGOPHER" then the result is ["gcc", "-DGOPHER"]. -func (b *Builder) compilerExe(envValue string, def string) []string { +func (b *Builder) compilerExe(envValue string, def string, filtered bool) []string { compiler := strings.Fields(envValue) if len(compiler) == 0 { compiler = []string{def} } + if filtered { + return append(compiler[0:1], filterCompilerFlags(compiler[1:])...) + } return compiler } @@ -1920,8 +1925,23 @@ func envList(key, def string) []string { return strings.Fields(v) } +var filterFlags = os.Getenv("CGO_PEDANTIC") == "" + +func filterCompilerFlags(flags []string) []string { + var newflags []string + if !filterFlags { + return flags + } + for _, flag := range flags { + if strings.HasPrefix(flag, "-m") { + newflags = append(newflags, flag) + } + } + return newflags +} + // CFlags returns the flags to use when invoking the C, C++ or Fortran compilers, or cgo. -func (b *Builder) CFlags(p *load.Package) (cppflags, cflags, cxxflags, fflags, ldflags []string, err error) { +func (b *Builder) CFlags(p *load.Package, filtered bool) (cppflags, cflags, cxxflags, fflags, ldflags []string, err error) { defaults := "-g -O2" if cppflags, err = buildFlags("CPPFLAGS", "", p.CgoCPPFLAGS, checkCompilerFlags); err != nil { @@ -1939,6 +1959,13 @@ func (b *Builder) CFlags(p *load.Package) (cppflags, cflags, cxxflags, fflags, l if ldflags, err = buildFlags("LDFLAGS", defaults, p.CgoLDFLAGS, checkLinkerFlags); err != nil { return } + if filtered { + cppflags = filterCompilerFlags(cppflags) + cflags = filterCompilerFlags(cflags) + cxxflags = filterCompilerFlags(cxxflags) + fflags = filterCompilerFlags(fflags) + ldflags = filterCompilerFlags(ldflags) + } return } @@ -1954,7 +1981,7 @@ var cgoRe = regexp.MustCompile(`[/\\:]`) func (b *Builder) cgo(a *Action, cgoExe, objdir string, pcCFLAGS, pcLDFLAGS, cgofiles, gccfiles, gxxfiles, mfiles, ffiles []string) (outGo, outObj []string, err error) { p := a.Package - cgoCPPFLAGS, cgoCFLAGS, cgoCXXFLAGS, cgoFFLAGS, cgoLDFLAGS, err := b.CFlags(p) + cgoCPPFLAGS, cgoCFLAGS, cgoCXXFLAGS, cgoFFLAGS, cgoLDFLAGS, err := b.CFlags(p, false) if err != nil { return nil, nil, err } @@ -2306,7 +2333,7 @@ func (b *Builder) swigIntSize(objdir string) (intsize string, err error) { // Run SWIG on one SWIG input file. func (b *Builder) swigOne(a *Action, p *load.Package, file, objdir string, pcCFLAGS []string, cxx bool, intgosize string) (outGo, outC string, err error) { - cgoCPPFLAGS, cgoCFLAGS, cgoCXXFLAGS, _, _, err := b.CFlags(p) + cgoCPPFLAGS, cgoCFLAGS, cgoCXXFLAGS, _, _, err := b.CFlags(p, false) if err != nil { return "", "", err } -- 2.14.1