gnu: glibc: Add "static" output.

This shrinks glibc:out from 37 MiB to 29 MiB.

* gnu/packages/base.scm (glibc/linux)[outputs]: Add "static".
[arguments]: Add #:modules.  Add 'move-static-libs' phase.
* gnu/packages/commencement.scm (static-bash-for-glibc): Augment
 #:configure-flags to pass "-L LIBC:STATIC".  Add the "static" output of
GLIBC-FINAL to 'inputs'.
(%boot2-inputs, %final-inputs): Likewise.
(canonical-package): Adjust to deal with multiple-output packages.
* gnu/packages/cross-base.scm (cross-gcc): Add the "static" output of
LIBC to 'native-inputs'.

gnu/packages/base.scm

@@ -542,7 +542,8 @@ store.")
    ;; users should automatically pull Linux headers as well.
    (propagated-inputs `(("kernel-headers" ,linux-libre-headers)))
 
-   (outputs '("out" "debug"))
+   (outputs '("out" "debug"
+              "static"))                          ;9 MiB of .a files
 
    (arguments
     `(#:out-of-source? #t
@@ -553,6 +554,11 @@ store.")
       ;; RUNPATH checks.
       #:validate-runpath? #f
 
+      #:modules ((ice-9 ftw)
+                 (srfi srfi-26)
+                 (guix build utils)
+                 (guix build gnu-build-system))
+
       #:configure-flags
       (list "--enable-add-ons"
             "--sysconfdir=/etc"
@@ -657,7 +663,46 @@ store.")
                          ;; "bilingual" eval/exec magic at the top of the file.
                          "")
                         (("exec @PERL@")
-                         "exec perl"))))))))
+                         "exec perl")))))
+
+                 (add-after 'install 'move-static-libs
+                   (lambda* (#:key outputs #:allow-other-keys)
+                     ;; Move static libraries to the "static" output.
+                     (define (static-library? file)
+                       ;; Return true if FILE is a static library.  The
+                       ;; "_nonshared.a" files are referred to by libc.so,
+                       ;; libpthread.so, etc., which are in fact linker
+                       ;; scripts.
+                       (and (string-suffix? ".a" file)
+                            (not (string-contains file "_nonshared"))))
+
+                     (define (linker-script? file)
+                       ;; Guess whether FILE, a ".a" file, is actually a
+                       ;; linker script.
+                       (and (not (ar-file? file))
+                            (not (elf-file? file))))
+
+                     (let* ((out    (assoc-ref outputs "out"))
+                            (lib    (string-append out "/lib"))
+                            (files  (scandir lib static-library?))
+                            (static (assoc-ref outputs "static"))
+                            (slib   (string-append static "/lib")))
+                       (mkdir-p slib)
+                       (for-each (lambda (base)
+                                   (rename-file (string-append lib "/" base)
+                                                (string-append slib "/" base)))
+                                 files)
+
+                       ;; Usually libm.a is a linker script so we need to
+                       ;; change the file names in there to refer to STATIC
+                       ;; instead of OUT.
+                       (for-each (lambda (ld-script)
+                                   (substitute* ld-script
+                                     ((out) static)))
+                                 (filter linker-script?
+                                         (map (cut string-append slib "/" <>)
+                                              files)))
+                       #t))))))
 
    (inputs `(("static-bash" ,static-bash)))
 

gnu/packages/commencement.scm

@@ -583,12 +583,24 @@ exec ~a/bin/~a-~a -B~a/lib -Wl,-dynamic-linker -Wl,~a/~a \"$@\"~%"
   (let* ((gcc  (cross-gcc-wrapper gcc-boot0 binutils-boot0
                                   glibc-final-with-bootstrap-bash
                                   (car (assoc-ref %boot1-inputs "bash"))))
-         (bash (package (inherit static-bash)
+         (bash (package
+                 (inherit static-bash)
                  (arguments
-                  `(#:guile ,%bootstrap-guile
+                  (substitute-keyword-arguments
-                    ,@(package-arguments static-bash)))))
+                      (package-arguments static-bash)
+                    ((#:guile _ #f)
+                     '%bootstrap-guile)
+                    ((#:configure-flags flags '())
+                     ;; Add a '-L' flag so that the pseudo-cross-ld of
+                     ;; BINUTILS-BOOT0 can find libc.a.
+                     `(append ,flags
+                              (list (string-append "LDFLAGS=-static -L"
+                                                   (assoc-ref %build-inputs
+                                                              "libc:static")
+                                                   "/lib"))))))))
          (inputs `(("gcc" ,gcc)
                    ("libc" ,glibc-final-with-bootstrap-bash)
+                   ("libc:static" ,glibc-final-with-bootstrap-bash "static")
                    ,@(fold alist-delete %boot1-inputs
                            '("gcc" "libc")))))
     (package-with-bootstrap-guile
@@ -663,6 +675,7 @@ exec ~a/bin/~a-~a -B~a/lib -Wl,-dynamic-linker -Wl,~a/~a \"$@\"~%"
 (define %boot2-inputs
   ;; 3rd stage inputs.
   `(("libc" ,glibc-final)
+    ("libc:static" ,glibc-final "static")
     ("gcc" ,gcc-boot0-wrapped)
     ,@(fold alist-delete %boot1-inputs '("libc" "gcc"))))
 
@@ -923,12 +936,13 @@ exec ~a/bin/~a-~a -B~a/lib -Wl,-dynamic-linker -Wl,~a/~a \"$@\"~%"
       ("binutils" ,binutils-final)
       ("gcc" ,gcc-final)
       ("libc" ,glibc-final)
+      ("libc:static" ,glibc-final "static")
       ("locales" ,glibc-utf8-locales-final))))
 
 (define-public canonical-package
   (let ((name->package (fold (lambda (input result)
                                (match input
-                                 ((_ package)
+                                 ((_ package . outputs)
                                   (vhash-cons (package-full-name package)
                                               package result))))
                              vlist-null

gnu/packages/cross-base.scm

@@ -248,6 +248,7 @@ target that libc."
                    ,@inputs)))
             (libc
              `(("libc" ,libc)
+               ("libc:static" ,libc "static")
                ("xkernel-headers"                ;the target headers
                 ,@(assoc-ref (package-propagated-inputs libc)
                              "kernel-headers"))