[bug#50227] [PATCH] build-system/go: Trim store references using the native compiler option.

[Marius Bakke <marius@gnu.org>]

* guix/build/go-build-system.scm (build): Add '-trimpath' to the 'go install'
invocation.
(remove-store-references, remove-go-references): Remove procedures.
(%standard-phases): Don't include remove-go-references.
* gnu/packages/docker.scm (docker)[arguments]: Add the '-trimpath' option to
the build flags.  Remove phase remove-go-references.
* gnu/packages/uucp.scm (nncp)[arguments]: Likewise.
---
 gnu/packages/docker.scm        |  7 ++--
 gnu/packages/uucp.scm          |  8 ++--
 guix/build/go-build-system.scm | 70 +++-------------------------------
 3 files changed, 14 insertions(+), 71 deletions(-)

diff --git a/gnu/packages/docker.scm b/gnu/packages/docker.scm
index 8bac1b89ce..108f355aa7 100644
--- a/gnu/packages/docker.scm
+++ b/gnu/packages/docker.scm
@@ -535,6 +535,8 @@ built-in registry server of Docker.")
              ;; Respectively, strip the symbol table and debug
              ;; information, and the DWARF symbol table.
              (setenv "LDFLAGS" "-s -w")
+             ;; Trim store references from the compiled binary.
+             (setenv "BUILDFLAGS" "-trimpath")
              ;; Make build faster
              (setenv "GOCACHE" "/tmp")
              #t))
@@ -568,10 +570,7 @@ built-in registry server of Docker.")
                (install-file "bundles/dynbinary-daemon/dockerd" out-bin)
                (install-file (string-append "bundles/dynbinary-daemon/dockerd-"
                                             (getenv "VERSION"))
-                             out-bin)
-               #t)))
-         (add-after 'install 'remove-go-references
-           (assoc-ref go:%standard-phases 'remove-go-references)))))
+                             out-bin)))))))
     (inputs
      `(("btrfs-progs" ,btrfs-progs)
        ("containerd" ,containerd)       ; for containerd-shim
diff --git a/gnu/packages/uucp.scm b/gnu/packages/uucp.scm
index 120417dea1..9d39c88fe5 100644
--- a/gnu/packages/uucp.scm
+++ b/gnu/packages/uucp.scm
@@ -127,6 +127,10 @@ between computers.")
              (substitute* (list "bin/default.do" "bin/hjson-cli.do" "test.do")
                ((" -mod=vendor") "")
                ((" -m") ""))
+             (substitute* (list "bin/default.do" "bin/hjson-cli.do")
+               ;; Prevent reference to the Go inputs in the compiled binaries.
+               (("\\$GO build")
+                "$GO build -trimpath"))
              ;; Use the correct module path. `go list` does not report the
              ;; correct module path since we have moved the source files.
              (substitute* "bin/default.do"
@@ -138,9 +142,7 @@ between computers.")
          (replace 'check
            (lambda* (#:key tests? #:allow-other-keys)
              (when tests?
-               (invoke "contrib/do" "-c" "test"))))
-         (add-after 'install 'remove-go-references
-           (assoc-ref go:%standard-phases 'remove-go-references)))))
+               (invoke "contrib/do" "-c" "test")))))))
     (inputs
      `(("go-github-com-davecgh-go-xdr" ,go-github-com-davecgh-go-xdr)
        ("go-github-com-dustin-go-humanize" ,go-github-com-dustin-go-humanize)
diff --git a/guix/build/go-build-system.scm b/guix/build/go-build-system.scm
index 37936fe5ca..fc5ee39c8d 100644
--- a/guix/build/go-build-system.scm
+++ b/guix/build/go-build-system.scm
@@ -28,8 +28,6 @@
   #:use-module (ice-9 match)
   #:use-module (ice-9 ftw)
   #:use-module (srfi srfi-1)
-  #:use-module (rnrs io ports)
-  #:use-module (rnrs bytevectors)
   #:export (%standard-phases
             go-build))
 
@@ -47,12 +45,9 @@
 ;; structure called a 'workspace' [1].  This workspace can be found by Go via
 ;; the GOPATH environment variable.  Typically, all Go source code and compiled
 ;; objects are kept in a single workspace, but GOPATH may be a list of
-;; directories [2].  In this go-build-system we create a file system union of
-;; the Go-language dependencies. Previously, we made GOPATH a list of store
-;; directories, but stopped because Go programs started keeping references to
-;; these directories in Go 1.11:
-;; <https://bugs.gnu.org/33620>.
-;;
+;; directories [2], which we rely on here, with the caveat that the current
+;; package must appear first on GOPATH.
+;
 ;; Go software, whether a package or a command, is uniquely named using an
 ;; 'import path'.  The import path is based on the URL of the software's source.
 ;; Because most source code is provided over the internet, the import path is
@@ -88,7 +83,6 @@
 ;; a tmpdir when creating the inputs union.
 ;; * Use Go modules [4]
 ;; * Re-use compiled packages [5]
-;; * Stop needing remove-go-references (-trimpath ? )
 ;; * Remove module packages, only offering the full Git repos? This is
 ;; more idiomatic, I think, because Go downloads Git repos, not modules.
 ;; What are the trade-offs?
@@ -194,6 +188,8 @@ unpacking."
       (apply invoke "go" "install"
               "-v" ; print the name of packages as they are compiled
               "-x" ; print each command as it is invoked
+              ;; Trim store references from the compiled binaries.
+              "-trimpath"
               ;; Respectively, strip the symbol table and debug
               ;; information, and the DWARF symbol table.
               "-ldflags=-s -w"
@@ -236,59 +232,6 @@ the standard install-license-files phase to first enter the correct directory."
                                                     unpack-path))
     (apply (assoc-ref gnu:%standard-phases 'install-license-files) args)))
 
-(define* (remove-store-reference file file-name
-                                  #:optional (store (%store-directory)))
-  "Remove from FILE occurrences of FILE-NAME in STORE; return #t when FILE-NAME
-is encountered in FILE, #f otherwise. This implementation reads FILE one byte at
-a time, which is slow. Instead, we should use the Boyer-Moore string search
-algorithm; there is an example in (guix build grafts)."
-  (define pattern
-    (string-take file-name
-                 (+ 34 (string-length (%store-directory)))))
-
-  (with-fluids ((%default-port-encoding #f))
-    (with-atomic-file-replacement file
-      (lambda (in out)
-        ;; We cannot use `regexp-exec' here because it cannot deal with
-        ;; strings containing NUL characters.
-        (format #t "removing references to `~a' from `~a'...~%" file-name file)
-        (setvbuf in 'block 65536)
-        (setvbuf out 'block 65536)
-        (fold-port-matches (lambda (match result)
-                             (put-bytevector out (string->utf8 store))
-                             (put-u8 out (char->integer #\/))
-                             (put-bytevector out
-                                             (string->utf8
-                                              "eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee-"))
-                             #t)
-                           #f
-                           pattern
-                           in
-                           (lambda (char result)
-                             (put-u8 out (char->integer char))
-                             result))))))
-
-(define* (remove-go-references #:key allow-go-reference?
-                               inputs outputs #:allow-other-keys)
-  "Remove any references to the Go compiler from the compiled Go executable
-files in OUTPUTS."
-;; We remove this spurious reference to save bandwidth when installing Go
-;; executables. It would be better to not embed the reference in the first
-;; place, but I'm not sure how to do that. The subject was discussed at:
-;; <https://lists.gnu.org/archive/html/guix-devel/2017-10/msg00207.html>
-  (if allow-go-reference?
-    #t
-    (let ((go (assoc-ref inputs "go"))
-          (bin "/bin"))
-      (for-each (lambda (output)
-                  (when (file-exists? (string-append (cdr output)
-                                                     bin))
-                    (for-each (lambda (file)
-                                (remove-store-reference file go))
-                              (find-files (string-append (cdr output) bin)))))
-                outputs)
-      #t)))
-
 (define %standard-phases
   (modify-phases gnu:%standard-phases
     (delete 'bootstrap)
@@ -299,8 +242,7 @@ files in OUTPUTS."
     (replace 'build build)
     (replace 'check check)
     (replace 'install install)
-    (replace 'install-license-files install-license-files)
-    (add-after 'install 'remove-go-references remove-go-references)))
+    (replace 'install-license-files install-license-files)))
 
 (define* (go-build #:key inputs (phases %standard-phases)
                       #:allow-other-keys #:rest args)
-- 
2.31.1