cmd/go: remove cross-package assembly reference discovery

This removes the special case for finding assembly references to Go
symbols in runtime and runtime/internal/atomic. These are no longer
necessary because we've now marked all symbols in these packages that
must be accessible from assembly in other packages.

Fixes #31230.

Change-Id: I70c90b70e13b922a6669f3d46c53347f98d6fc3f
Reviewed-on: https://go-review.googlesource.com/c/go/+/179863
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

diff --git a/src/cmd/go/internal/work/exec.go b/src/cmd/go/internal/work/exec.go
index 6f2d319bc22f006001471bbad14dbf076f677346..c1bb9416cbba5d716c24ee9387990237e9de1917 100644 (file)
--- a/src/cmd/go/internal/work/exec.go
+++ b/src/cmd/go/internal/work/exec.go
@@ -1682,25 +1682,6 @@ func (b *Builder) writeFile(file string, text []byte) error {
        return ioutil.WriteFile(file, text, 0666)
 }
 
-// appendFile appends the text to file.
-func (b *Builder) appendFile(file string, text []byte) error {
-       if cfg.BuildN || cfg.BuildX {
-               b.Showcmd("", "cat >>%s << 'EOF' # internal\n%sEOF", file, text)
-       }
-       if cfg.BuildN {
-               return nil
-       }
-       f, err := os.OpenFile(file, os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0666)
-       if err != nil {
-               return err
-       }
-       defer f.Close()
-       if _, err = f.Write(text); err != nil {
-               return err
-       }
-       return f.Close()
-}
-
 // Install the cgo export header file, if there is one.
 func (b *Builder) installHeader(a *Action) error {
        src := a.Objdir + "_cgo_install.h"

diff --git a/src/cmd/go/internal/work/gc.go b/src/cmd/go/internal/work/gc.go
index 6ec24b28555dd63ed83eb3b3e7bd0d624114c893..86322946a6113484ce2a61c3b00b9eacd0d4121b 100644 (file)
--- a/src/cmd/go/internal/work/gc.go
+++ b/src/cmd/go/internal/work/gc.go
@@ -309,55 +309,6 @@ func (gcToolchain) symabis(b *Builder, a *Action, sfiles []string) (string, erro
                }
        }
 
-       // Gather known cross-package references from assembly code.
-       var otherPkgs []string
-       if p.ImportPath == "runtime" {
-               // Assembly in the following packages references
-               // symbols in runtime.
-               otherPkgs = []string{"syscall", "internal/syscall/unix", "runtime/cgo"}
-       } else if p.ImportPath == "runtime/internal/atomic" {
-               // sync/atomic is an assembly wrapper around
-               // runtime/internal/atomic.
-               otherPkgs = []string{"sync/atomic"}
-       }
-       for _, p2name := range otherPkgs {
-               p2 := load.LoadImportWithFlags(p2name, p.Dir, p, &load.ImportStack{}, nil, 0)
-               if len(p2.SFiles) == 0 {
-                       continue
-               }
-
-               symabis2 := a.Objdir + "symabis2"
-               if err := mkSymabis(p2, p2.SFiles, symabis2); err != nil {
-                       return "", err
-               }
-
-               // Filter out just the symbol refs and append them to
-               // the symabis file.
-               if cfg.BuildN {
-                       // -x will print the lines from symabis2 that are actually appended
-                       // to symabis. With -n, we don't know what those lines will be.
-                       b.Showcmd("", `grep '^ref' <%s | grep -v '^ref\s*""\.' >>%s`, symabis2, a.Objdir+"symabis")
-                       continue
-               }
-               abis2, err := ioutil.ReadFile(symabis2)
-               if err != nil {
-                       return "", err
-               }
-               var refs bytes.Buffer
-               for _, line := range strings.Split(string(abis2), "\n") {
-                       fs := strings.Fields(line)
-                       if len(fs) >= 2 && fs[0] == "ref" && !strings.HasPrefix(fs[1], `"".`) {
-                               fmt.Fprintf(&refs, "%s\n", line)
-                       }
-               }
-               if refs.Len() != 0 {
-                       symabis = a.Objdir + "symabis"
-                       if err := b.appendFile(symabis, refs.Bytes()); err != nil {
-                               return "", err
-                       }
-               }
-       }
-
        return symabis, nil
 }