;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2012, 2013, 2014, 2015 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2014 Andreas Enge <andreas@enge.fr>
;;; Copyright © 2012 Nikita Karetnikov <nikita@karetnikov.org>
;;; Copyright © 2014, 2015 Mark H Weaver <mhw@netris.org>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.

(define-module (gnu packages commencement)
  #:use-module ((guix licenses)
                #:select (gpl3+ lgpl2.0+ public-domain))
  #:use-module (gnu packages bootstrap)
  #:use-module (gnu packages base)
  #:use-module (gnu packages bash)
  #:use-module (gnu packages gcc)
  #:use-module (gnu packages m4)
  #:use-module (gnu packages file)
  #:use-module (gnu packages gawk)
  #:use-module (gnu packages bison)
  #:use-module (gnu packages guile)
  #:use-module (gnu packages gettext)
  #:use-module (gnu packages multiprecision)
  #:use-module (gnu packages compression)
  #:use-module (gnu packages perl)
  #:use-module (gnu packages linux)
  #:use-module (gnu packages texinfo)
  #:use-module (gnu packages pkg-config)
  #:use-module (guix packages)
  #:use-module (guix download)
  #:use-module (guix build-system gnu)
  #:use-module (guix build-system trivial)
  #:use-module (guix utils)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-26)
  #:use-module (ice-9 vlist)
  #:use-module (ice-9 match))

;;; Commentary:
;;;
;;; This is the commencement, this is where things start.  Before the
;;; commencement, of course, there's the 'bootstrap' module, which provides us
;;; with the initial binaries.  This module uses those bootstrap binaries to
;;; actually build up the whole tool chain that make up the implicit inputs of
;;; 'gnu-build-system'.
;;;
;;; To avoid circular dependencies, this module should not be imported
;;; directly from anywhere.
;;;
;;; Code:

(define gnu-make-boot0
  (package-with-bootstrap-guile
   (package (inherit gnu-make)
     (name "make-boot0")
     (arguments
      `(#:guile ,%bootstrap-guile
        #:implicit-inputs? #f
        #:tests? #f                  ; cannot run "make check"
        ,@(substitute-keyword-arguments (package-arguments gnu-make)
            ((#:phases phases)
             `(alist-replace
               'build (lambda _
                        (zero? (system* "./build.sh")))
               (alist-replace
                'install (lambda* (#:key outputs #:allow-other-keys)
                           (let* ((out (assoc-ref outputs "out"))
                                  (bin (string-append out "/bin")))
                             (mkdir-p bin)
                             (copy-file "make"
                                        (string-append bin "/make"))))
                ,phases))))))
     (native-inputs '())                          ; no need for 'pkg-config'
     (inputs %bootstrap-inputs))))

(define diffutils-boot0
  (package-with-bootstrap-guile
   (let ((p (package-with-explicit-inputs diffutils
                                          `(("make" ,gnu-make-boot0)
                                            ,@%bootstrap-inputs)
                                          #:guile %bootstrap-guile)))
     (package (inherit p)
       (arguments `(#:tests? #f         ; the test suite needs diffutils
                    ,@(package-arguments p)))))))

(define findutils-boot0
  (package-with-bootstrap-guile
   (package-with-explicit-inputs findutils
                                 `(("make" ,gnu-make-boot0)
                                   ("diffutils" ,diffutils-boot0) ; for tests
                                   ,@%bootstrap-inputs)
                                 (current-source-location)
                                 #:guile %bootstrap-guile)))

(define file-boot0
  (package-with-bootstrap-guile
   (package-with-explicit-inputs file
                                 `(("make" ,gnu-make-boot0)
                                   ,@%bootstrap-inputs)
                                 (current-source-location)
                                 #:guile %bootstrap-guile)))


(define %boot0-inputs
  `(("make" ,gnu-make-boot0)
    ("diffutils" ,diffutils-boot0)
    ("findutils" ,findutils-boot0)
    ("file" ,file-boot0)
    ,@%bootstrap-inputs))

(define* (boot-triplet #:optional (system (%current-system)))
  ;; Return the triplet used to create the cross toolchain needed in the
  ;; first bootstrapping stage.
  (nix-system->gnu-triplet system "guix"))

;; Following Linux From Scratch, build a cross-toolchain in stage 0.  That
;; toolchain actually targets the same OS and arch, but it has the advantage
;; of being independent of the libc and tools in %BOOTSTRAP-INPUTS, since
;; GCC-BOOT0 (below) is built without any reference to the target libc.

(define binutils-boot0
  (package-with-bootstrap-guile
   (package (inherit binutils)
     (name "binutils-cross-boot0")
     (arguments
      `(#:guile ,%bootstrap-guile
        #:implicit-inputs? #f

        #:modules ((guix build gnu-build-system)
                   (guix build utils)
                   (ice-9 ftw))                    ; for 'scandir'
        #:phases (alist-cons-after
                  'install 'add-symlinks
                  (lambda* (#:key outputs #:allow-other-keys)
                    ;; The cross-gcc invokes 'as', 'ld', etc, without the
                    ;; triplet prefix, so add symlinks.
                    (let ((out (assoc-ref outputs "out"))
                          (triplet-prefix (string-append ,(boot-triplet) "-")))
                      (define (has-triplet-prefix? name)
                        (string-prefix? triplet-prefix name))
                      (define (remove-triplet-prefix name)
                        (substring name (string-length triplet-prefix)))
                      (with-directory-excursion (string-append out "/bin")
                        (for-each (lambda (name)
                                    (symlink name (remove-triplet-prefix name)))
                                  (scandir "." has-triplet-prefix?)))
                      #t))
                  %standard-phases)

        ,@(substitute-keyword-arguments (package-arguments binutils)
            ((#:configure-flags cf)
             `(cons ,(string-append "--target=" (boot-triplet))
                    ,cf)))))
     (inputs %boot0-inputs))))

(define gcc-boot0
  (package-with-bootstrap-guile
   (package (inherit gcc)
     (name "gcc-cross-boot0")
     (arguments
      `(#:guile ,%bootstrap-guile
        #:implicit-inputs? #f
        #:modules ((guix build gnu-build-system)
                   (guix build utils)
                   (ice-9 regex)
                   (srfi srfi-1)
                   (srfi srfi-26))
        ,@(substitute-keyword-arguments (package-arguments gcc)
            ((#:configure-flags flags)
             `(append (list ,(string-append "--target=" (boot-triplet))

                            ;; No libc yet.
                            "--without-headers"

                            ;; Disable features not needed at this stage.
                            "--disable-shared"
                            "--enable-languages=c,c++"

                            ;; libstdc++ cannot be built at this stage
                            ;; ("Link tests are not allowed after
                            ;; GCC_NO_EXECUTABLES.").
                            "--disable-libstdc++-v3"

                            "--disable-threads"
                            "--disable-libmudflap"
                            "--disable-libatomic"
                            "--disable-libsanitizer"
                            "--disable-libitm"
                            "--disable-libgomp"
                            "--disable-libcilkrts"
                            "--disable-libvtv"
                            "--disable-libssp"
                            "--disable-libquadmath"
                            "--disable-decimal-float")
                      (remove (cut string-match "--enable-languages.*" <>)
                              ,flags)))
            ((#:phases phases)
             `(alist-cons-after
               'unpack 'unpack-gmp&co
               (lambda* (#:key inputs #:allow-other-keys)
                 (let ((gmp  (assoc-ref %build-inputs "gmp-source"))
                       (mpfr (assoc-ref %build-inputs "mpfr-source"))
                       (mpc  (assoc-ref %build-inputs "mpc-source")))

                   ;; To reduce the set of pre-built bootstrap inputs, build
                   ;; GMP & co. from GCC.
                   (for-each (lambda (source)
                               (or (zero? (system* "tar" "xvf" source))
                                   (error "failed to unpack tarball"
                                          source)))
                             (list gmp mpfr mpc))

                   ;; Create symlinks like `gmp' -> `gmp-x.y.z'.
                   ,@(map (lambda (lib)
                            ;; Drop trailing letters, as gmp-6.0.0a unpacks
                            ;; into gmp-6.0.0.
                            `(symlink ,(string-trim-right
                                        (package-full-name lib)
                                        char-set:letter)
                                      ,(package-name lib)))
                          (list gmp mpfr mpc))))
               (alist-cons-after
                'install 'symlink-libgcc_eh
                (lambda* (#:key outputs #:allow-other-keys)
                  (let ((out (assoc-ref outputs "lib")))
                    ;; Glibc wants to link against libgcc_eh, so provide
                    ;; it.
                    (with-directory-excursion
                        (string-append out "/lib/gcc/"
                                       ,(boot-triplet)
                                       "/" ,(package-version gcc))
                      (symlink "libgcc.a" "libgcc_eh.a"))))
                ,phases))))))

     (inputs `(("gmp-source" ,(package-source gmp))
               ("mpfr-source" ,(package-source mpfr))
               ("mpc-source" ,(package-source mpc))
               ("binutils-cross" ,binutils-boot0)

               ;; Call it differently so that the builder can check whether
               ;; the "libc" input is #f.
               ("libc-native" ,@(assoc-ref %boot0-inputs "libc"))
               ,@(alist-delete "libc" %boot0-inputs)))

     ;; No need for Texinfo at this stage.
     (native-inputs (alist-delete "texinfo"
                                  (package-native-inputs gcc))))))

(define perl-boot0
  (package-with-bootstrap-guile
   (package-with-explicit-inputs perl
                                 %boot0-inputs
                                 (current-source-location)
                                 #:guile %bootstrap-guile)))

(define (linux-libre-headers-boot0)
  "Return Linux-Libre header files for the bootstrap environment."
  ;; Note: this is wrapped in a thunk to nicely handle circular dependencies
  ;; between (gnu packages linux) and this module.
  (package-with-bootstrap-guile
   (package (inherit linux-libre-headers)
     (arguments `(#:guile ,%bootstrap-guile
                  #:implicit-inputs? #f
                  ,@(package-arguments linux-libre-headers)))
     (native-inputs
      `(("perl" ,perl-boot0)
        ,@%boot0-inputs)))))

(define texinfo-boot0
  ;; Texinfo used to build libc's manual.
  ;; We build without ncurses because it fails to build at this stage, and
  ;; because we don't need the stand-alone Info reader.
  ;; Also, use %BOOT0-INPUTS to avoid building Perl once more.
  (let ((texinfo (package (inherit texinfo)
                   (native-inputs '())
                   (inputs (alist-delete "ncurses" (package-inputs texinfo))))))
    (package-with-bootstrap-guile
     (package-with-explicit-inputs texinfo %boot0-inputs
                                   (current-source-location)
                                   #:guile %bootstrap-guile))))

(define %boot1-inputs
  ;; 2nd stage inputs.
  `(("gcc" ,gcc-boot0)
    ("binutils-cross" ,binutils-boot0)
    ,@(alist-delete "binutils" %boot0-inputs)))

(define glibc-final-with-bootstrap-bash
  ;; The final libc, "cross-built".  If everything went well, the resulting
  ;; store path has no dependencies.  Actually, the really-final libc is
  ;; built just below; the only difference is that this one uses the
  ;; bootstrap Bash.
  (package-with-bootstrap-guile
   (package (inherit glibc)
     (name "glibc-intermediate")
     (arguments
      `(#:guile ,%bootstrap-guile
        #:implicit-inputs? #f

        ,@(substitute-keyword-arguments (package-arguments glibc)
            ((#:configure-flags flags)
             `(append (list ,(string-append "--host=" (boot-triplet))
                            ,(string-append "--build="
                                            (nix-system->gnu-triplet))

                            ;; Build Sun/ONC RPC support.  In particular,
                            ;; install rpc/*.h.
                            "--enable-obsolete-rpc")
                      ,flags))
            ((#:phases phases)
             `(alist-cons-before
               'configure 'pre-configure
               (lambda* (#:key inputs #:allow-other-keys)
                 ;; Don't clobber CPATH with the bootstrap libc.
                 (setenv "NATIVE_CPATH" (getenv "CPATH"))
                 (unsetenv "CPATH")

                 ;; 'rpcgen' needs native libc headers to be built.
                 (substitute* "sunrpc/Makefile"
                   (("sunrpc-CPPFLAGS =.*" all)
                    (string-append "CPATH = $(NATIVE_CPATH)\n"
                                   "export CPATH\n"
                                   all "\n"))))
               ,phases)))))
     (propagated-inputs `(("linux-headers" ,(linux-libre-headers-boot0))))
     (native-inputs
      `(("texinfo" ,texinfo-boot0)
        ("perl" ,perl-boot0)))
     (inputs
      `(;; The boot inputs.  That includes the bootstrap libc.  We don't want
        ;; it in $CPATH, hence the 'pre-configure' phase above.
        ,@%boot1-inputs

        ;; A native GCC is needed to build `cross-rpcgen'.
        ("native-gcc" ,@(assoc-ref %boot0-inputs "gcc"))

        ;; Here, we use the bootstrap Bash, which is not satisfactory
        ;; because we don't want to depend on bootstrap tools.
        ("static-bash" ,@(assoc-ref %boot0-inputs "bash")))))))

(define (cross-gcc-wrapper gcc binutils glibc bash)
  "Return a wrapper for the pseudo-cross toolchain GCC/BINUTILS/GLIBC
that makes it available under the native tool names."
  (package (inherit gcc)
    (name (string-append (package-name gcc) "-wrapped"))
    (source #f)
    (build-system trivial-build-system)
    (outputs '("out"))
    (arguments
     `(#:guile ,%bootstrap-guile
       #:modules ((guix build utils))
       #:builder (begin
                   (use-modules (guix build utils))

                   (let* ((binutils (assoc-ref %build-inputs "binutils"))
                          (gcc      (assoc-ref %build-inputs "gcc"))
                          (libc     (assoc-ref %build-inputs "libc"))
                          (bash     (assoc-ref %build-inputs "bash"))
                          (out      (assoc-ref %outputs "out"))
                          (bindir   (string-append out "/bin"))
                          (triplet  ,(boot-triplet)))
                     (define (wrap-program program)
                       ;; GCC-BOOT0 is a libc-less cross-compiler, so it
                       ;; needs to be told where to find the crt files and
                       ;; the dynamic linker.
                       (call-with-output-file program
                         (lambda (p)
                           (format p "#!~a/bin/bash
exec ~a/bin/~a-~a -B~a/lib -Wl,-dynamic-linker -Wl,~a/~a \"$@\"~%"
                                   bash
                                   gcc triplet program
                                   libc libc
                                   ,(glibc-dynamic-linker))))

                       (chmod program #o555))

                     (mkdir-p bindir)
                     (with-directory-excursion bindir
                       (for-each (lambda (tool)
                                   (symlink (string-append binutils "/bin/"
                                                           triplet "-" tool)
                                            tool))
                                 '("ar" "ranlib"))
                       (for-each wrap-program '("gcc" "g++")))))))
    (native-inputs
     `(("binutils" ,binutils)
       ("gcc" ,gcc)
       ("libc" ,glibc)
       ("bash" ,bash)))
    (inputs '())))

(define bison-boot1
  ;; XXX: This Bison is needed to rebuild Bash's parser, which is modified by
  ;; its CVE patches.  Remove it when it's no longer needed.
  (let* ((m4    (package-with-bootstrap-guile
                 (package-with-explicit-inputs m4 %boot0-inputs
                                               (current-source-location)
                                               #:guile %bootstrap-guile)))
         (bison (package (inherit bison)
                  (native-inputs `(("perl" ,perl-boot0)))
                  (propagated-inputs `(("m4" ,m4)))
                  (inputs '())                    ;remove Flex...
                  (arguments '(#:tests? #f)))))   ;... and thus disable tests
   (package-with-bootstrap-guile
    (package-with-explicit-inputs bison %boot0-inputs
                                  (current-source-location)
                                  #:guile %bootstrap-guile))))

(define static-bash-for-glibc
  ;; A statically-linked Bash to be used by GLIBC-FINAL in system(3) & co.
  (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)
                 (native-inputs `(("bison" ,bison-boot1)))
                 (arguments
                  `(#:guile ,%bootstrap-guile
                    ,@(package-arguments static-bash))))))
    (package-with-bootstrap-guile
     (package-with-explicit-inputs bash
                                   `(("gcc" ,gcc)
                                     ("libc" ,glibc-final-with-bootstrap-bash)
                                     ,@(fold alist-delete %boot1-inputs
                                             '("gcc" "libc")))
                                   (current-source-location)))))

(define gettext-boot0
  ;; A minimal gettext used during bootstrap.
  (let ((gettext-minimal
         (package (inherit gnu-gettext)
           (name "gettext-boot0")
           (inputs '())                           ;zero dependencies
           (arguments
            (substitute-keyword-arguments
                `(#:tests? #f
                  ,@(package-arguments gnu-gettext))
              ((#:phases phases)
               `(modify-phases ,phases
                  ;; Build only the tools.
                  (add-after 'unpack 'chdir
                             (lambda _
                               (chdir "gettext-tools")))

                  ;; Some test programs require pthreads, which we don't have.
                  (add-before 'configure 'no-test-programs
                              (lambda _
                                (substitute* "tests/Makefile.in"
                                  (("^PROGRAMS =.*$")
                                   "PROGRAMS =\n"))
                                #t))

                  ;; Don't try to link against libexpat.
                  (delete 'link-expat)
                  (delete 'patch-tests))))))))
    (package-with-bootstrap-guile
     (package-with-explicit-inputs gettext-minimal
                                   %boot1-inputs
                                   (current-source-location)
                                   #:guile %bootstrap-guile))))

(define glibc-final
  ;; The final glibc, which embeds the statically-linked Bash built above.
  (package (inherit glibc-final-with-bootstrap-bash)
    (name "glibc")
    (inputs `(("static-bash" ,static-bash-for-glibc)
              ,@(alist-delete
                 "static-bash"
                 (package-inputs glibc-final-with-bootstrap-bash))))

    ;; This time we need 'msgfmt' to install all the libc.mo files.
    (native-inputs `(,@(package-native-inputs glibc-final-with-bootstrap-bash)
                     ("gettext" ,gettext-boot0)))

    ;; The final libc only refers to itself, but the 'debug' output contains
    ;; references to GCC-BOOT0 and to the Linux headers.  XXX: Would be great
    ;; if 'allowed-references' were per-output.
    (arguments
     `(#:allowed-references
       ,(cons* `(,gcc-boot0 "lib") (linux-libre-headers-boot0)
               static-bash-for-glibc
               (package-outputs glibc-final-with-bootstrap-bash))

       ,@(package-arguments glibc-final-with-bootstrap-bash)))))

(define gcc-boot0-wrapped
  ;; Make the cross-tools GCC-BOOT0 and BINUTILS-BOOT0 available under the
  ;; non-cross names.
  (cross-gcc-wrapper gcc-boot0 binutils-boot0 glibc-final
                     (car (assoc-ref %boot1-inputs "bash"))))

(define %boot2-inputs
  ;; 3rd stage inputs.
  `(("libc" ,glibc-final)
    ("gcc" ,gcc-boot0-wrapped)
    ,@(fold alist-delete %boot1-inputs '("libc" "gcc"))))

(define binutils-final
  (package-with-bootstrap-guile
   (package (inherit binutils)
     (arguments
      `(#:guile ,%bootstrap-guile
        #:implicit-inputs? #f
        #:allowed-references ("out" ,glibc-final)
        ,@(package-arguments binutils)))
     (inputs %boot2-inputs))))

(define libstdc++
  ;; Intermediate libstdc++ that will allow us to build the final GCC
  ;; (remember that GCC-BOOT0 cannot build libstdc++.)
  ;; TODO: Write in terms of 'make-libstdc++'.
  (package-with-bootstrap-guile
   (package (inherit gcc)
     (name "libstdc++")
     (arguments
      `(#:guile ,%bootstrap-guile
        #:implicit-inputs? #f

        #:out-of-source? #t
        #:phases (alist-cons-before
                  'configure 'chdir
                  (lambda _
                    (chdir "libstdc++-v3"))
                  %standard-phases)
        #:configure-flags `("--disable-shared"
                            "--disable-libstdcxx-threads"
                            "--disable-libstdcxx-pch"
                            ,(string-append "--with-gxx-include-dir="
                                            (assoc-ref %outputs "out")
                                            "/include"
                                            ;; "/include/c++/"
                                            ;; ,(package-version gcc)
                                            ))))
     (outputs '("out"))
     (inputs %boot2-inputs)
     (native-inputs '())
     (propagated-inputs '())
     (synopsis "GNU C++ standard library (intermediate)"))))

(define gcc-final
  ;; The final GCC.
  (package (inherit gcc-boot0)
    (name "gcc")

    ;; XXX: Currently #:allowed-references applies to all the outputs but the
    ;; "debug" output contains disallowed references, notably
    ;; linux-libre-headers.  Disable the debugging output to work around that.
    (outputs (delete "debug" (package-outputs gcc-boot0)))

    (arguments
     `(#:guile ,%bootstrap-guile
       #:implicit-inputs? #f

       #:allowed-references ("out" "lib"
                             ,glibc-final ,static-bash-for-glibc)

       ;; Things like libasan.so and libstdc++.so NEED ld.so for some
       ;; reason, but it is not in their RUNPATH.  This is a false
       ;; positive, so turn it off.
       #:validate-runpath? #f

       ;; Build again GMP & co. within GCC's build process, because it's hard
       ;; to do outside (because GCC-BOOT0 is a cross-compiler, and thus
       ;; doesn't honor $LIBRARY_PATH, which breaks `gnu-build-system'.)
       ,@(substitute-keyword-arguments (package-arguments gcc-boot0)
           ((#:configure-flags boot-flags)
            (let loop ((args (package-arguments gcc)))
              (match args
                ((#:configure-flags normal-flags _ ...)
                 normal-flags)
                ((_ rest ...)
                 (loop rest)))))
           ((#:make-flags flags)
            ;; Since $LIBRARY_PATH and $CPATH are not honored, add the
            ;; relevant flags.
            `(cons (string-append "CPPFLAGS=-I"
                                  (assoc-ref %build-inputs "libstdc++")
                                  "/include")
                   (map (lambda (flag)
                          (if (string-prefix? "LDFLAGS=" flag)
                              (string-append flag " -L"
                                             (assoc-ref %build-inputs "libstdc++")
                                             "/lib")
                              flag))
                        ,flags)))
           ((#:phases phases)
            `(alist-delete 'symlink-libgcc_eh ,phases)))))

    ;; This time we want Texinfo, so we get the manual.  Add
    ;; STATIC-BASH-FOR-GLIBC so that it's used in the final shebangs of
    ;; scripts such as 'mkheaders' and 'fixinc.sh' (XXX: who cares about these
    ;; scripts?).
    (native-inputs `(("texinfo" ,texinfo-boot0)
                     ("static-bash" ,static-bash-for-glibc)
                     ,@(package-native-inputs gcc-boot0)))

    (inputs `(("gmp-source" ,(bootstrap-origin (package-source gmp)))
              ("mpfr-source" ,(package-source mpfr))
              ("mpc-source" ,(package-source mpc))
              ("binutils" ,binutils-final)
              ("libstdc++" ,libstdc++)
              ,@%boot2-inputs))))

(define ld-wrapper-boot3
  ;; A linker wrapper that uses the bootstrap Guile.
  (make-ld-wrapper "ld-wrapper-boot3"
                   #:binutils binutils-final
                   #:guile %bootstrap-guile
                   #:bash (car (assoc-ref %boot2-inputs "bash"))))

(define %boot3-inputs
  ;; 4th stage inputs.
  `(("gcc" ,gcc-final)
    ("ld-wrapper" ,ld-wrapper-boot3)
    ,@(alist-delete "gcc" %boot2-inputs)))

(define bash-final
  ;; Link with `-static-libgcc' to make sure we don't retain a reference
  ;; to the bootstrap GCC.
  (package-with-bootstrap-guile
   (package-with-explicit-inputs (static-libgcc-package bash)
                                 %boot3-inputs
                                 (current-source-location)
                                 #:guile %bootstrap-guile)))

(define %boot4-inputs
  ;; Now use the final Bash.
  `(("bash" ,bash-final)
    ,@(alist-delete "bash" %boot3-inputs)))

(define-public guile-final
  (package-with-bootstrap-guile
   (package-with-explicit-inputs guile-2.0/fixed
                                 %boot4-inputs
                                 (current-source-location)
                                 #:guile %bootstrap-guile)))

(define glibc-utf8-locales-final
  ;; Now that we have GUILE-FINAL, build the UTF-8 locales.  They are needed
  ;; by the build processes afterwards so their 'scm_to_locale_string' works
  ;; with the full range of Unicode codepoints (remember
  ;; 'scm_to_locale_string' is called every time a string is passed to a C
  ;; function.)
  (package
    (inherit glibc-utf8-locales)
    (inputs `(("glibc" ,glibc-final)
              ("gzip"
               ,(package-with-explicit-inputs gzip %boot4-inputs
                                              (current-source-location)
                                              #:guile %bootstrap-guile))))))

(define (locale-proof-package p)
  "Return a new package based on P that ignores 'LOCPATH'.  The result is a
\"locale-proof\" package in the sense that it cannot end up loading locale
data that is not in the format its libc expects.  This is useful because the
locale binary format may change incompatibly between libc versions."
  (package
    (inherit p)
    (name (string-append (package-name p) "-lp"))
    (build-system trivial-build-system)
    (inputs `(("original" ,p)
              ("bash" ,bash-final)))
    (outputs '("out"))
    (arguments
     '(#:modules ((guix build utils))
       #:builder
       (begin
         (use-modules (guix build utils))

         (let* ((out      (assoc-ref %outputs "out"))
                (bin      (string-append out "/bin"))
                (bash     (assoc-ref %build-inputs "bash"))
                (binaries (assoc-ref %build-inputs "original"))
                (programs (find-files (string-append binaries "/bin"))))
           (define (wrap-program program)
             (let ((base (basename program)))
               (call-with-output-file base
                 (lambda (port)
                   (format port "#!~a/bin/sh
# Unset 'LOCPATH' so that the program does not end up loading incompatible
# locale data.
unset LOCPATH
exec \"~a\" \"$@\"\n"
                           bash program)))
               (chmod base #o755)))

           (mkdir-p bin)
           (with-directory-excursion bin
             (for-each wrap-program programs)
             #t)))))))

(define-public ld-wrapper
  ;; The final 'ld' wrapper, which uses the final Guile and Binutils.
  (package (inherit ld-wrapper-boot3)
    (name "ld-wrapper")
    (inputs `(("guile" ,guile-final)
              ("bash"  ,bash-final)
              ,@(fold alist-delete (package-inputs ld-wrapper-boot3)
                      '("guile" "bash"))))))

(define %boot5-inputs
  ;; Now with UTF-8 locales.  Since the locale binary format differs between
  ;; libc versions, we have to rebuild some of the packages so that they use
  ;; the new libc, which allows them to load locale data from
  ;; GLIBC-UTF8-LOCALES-FINAL (remember that the bootstrap binaries were built
  ;; with an older libc, which cannot load the new locale format.)  See
  ;; <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
  (let ((new-libc-package (compose package-with-bootstrap-guile
                                   (cut package-with-explicit-inputs <>
                                        %boot4-inputs
                                        (current-source-location)
                                        #:guile %bootstrap-guile))))
    `(("locales" ,glibc-utf8-locales-final)
      ("ld-wrapper" ,ld-wrapper)
      ("binutils" ,binutils-final)
      ("bash" ,bash-final)
      ("make" ,(new-libc-package gnu-make))

      ;; Some test suites (grep, Gnulib) use 'diff' to compare files in locale
      ;; encoding, so we need support this.
      ("diffutils" ,(new-libc-package diffutils))
      ("findutils" ,(new-libc-package findutils))

      ;; Grep's test suite uses 'timeout' from Coreutils to execute command,
      ;; and yet these commands need to see the valid 'LOCPATH'.
      ("coreutils" ,(new-libc-package coreutils-light))

      ;; We just wrap the remaining binaries (tar, gzip, xz, etc.)  so that
      ;; they ignore 'LOCPATH' (if they did not, they would be hit by an
      ;; assertion failure in loadlocale.c.)
      ("coreutils&co" ,(locale-proof-package %bootstrap-coreutils&co))

      ,@(fold alist-delete %boot4-inputs
              '("coreutils&co" "findutils" "diffutils" "make"
                "bash" "binutils-cross" "ld-wrapper")))))

(define gnu-make-final
  ;; The final GNU Make, which uses the final Guile.
  (package-with-bootstrap-guile
   (package-with-explicit-inputs gnu-make
                                 `(("guile" ,guile-final)
                                   ,@%boot5-inputs)
                                 (current-source-location))))

(define coreutils-final
  ;; The final Coreutils.  Treat them specially because some packages, such as
  ;; Findutils, keep a reference to the Coreutils they were built with.
  (package-with-bootstrap-guile
   (package-with-explicit-inputs coreutils
                                 %boot5-inputs
                                 (current-source-location)

                                 ;; Use the final Guile, linked against the
                                 ;; final libc with working iconv, so that
                                 ;; 'substitute*' works well when touching
                                 ;; test files in Gettext.
                                 #:guile guile-final)))

(define grep-final
  ;; The final grep.  Gzip holds a reference to it (via zgrep), so it must be
  ;; built before gzip.
  (package-with-bootstrap-guile
   (package-with-explicit-inputs grep
                                 %boot5-inputs
                                 (current-source-location)
                                 #:guile guile-final)))

(define %boot6-inputs
  ;; Now use the final Coreutils.
  `(("coreutils" ,coreutils-final)
    ("grep" ,grep-final)
    ,@%boot5-inputs))

(define-public %final-inputs
  ;; Final derivations used as implicit inputs by 'gnu-build-system'.  We
  ;; still use 'package-with-bootstrap-guile' so that the bootstrap tools are
  ;; used for origins that have patches, thereby avoiding circular
  ;; dependencies.
  (let ((finalize (compose package-with-bootstrap-guile
                           (cut package-with-explicit-inputs <> %boot6-inputs
                                (current-source-location)))))
    `(,@(map (match-lambda
              ((name package)
               (list name (finalize package))))
             `(("tar" ,tar)
               ("gzip" ,gzip)
               ("bzip2" ,bzip2)
               ("xz" ,xz)
               ("file" ,file)
               ("diffutils" ,diffutils)
               ("patch" ,patch)
               ("sed" ,sed)
               ("findutils" ,findutils)
               ("gawk" ,gawk)))
      ("grep" ,grep-final)
      ("coreutils" ,coreutils-final)
      ("make" ,gnu-make-final)
      ("bash" ,bash-final)
      ("ld-wrapper" ,ld-wrapper)
      ("binutils" ,binutils-final)
      ("gcc" ,gcc-final)
      ("libc" ,glibc-final)
      ("locales" ,glibc-utf8-locales-final))))

(define-public canonical-package
  (let ((name->package (fold (lambda (input result)
                               (match input
                                 ((_ package)
                                  (vhash-cons (package-full-name package)
                                              package result))))
                             vlist-null
                             `(("guile" ,guile-final)
                               ,@%final-inputs))))
    (lambda (package)
      "Return the 'canonical' variant of PACKAGE---i.e., if PACKAGE is one of
the implicit inputs of 'gnu-build-system', return that one, otherwise return
PACKAGE.

The goal is to avoid duplication in cases like GUILE-FINAL vs. GUILE-2.0,
COREUTILS-FINAL vs. COREUTILS, etc."
      ;; XXX: This doesn't handle dependencies of the final inputs, such as
      ;; libunistring, GMP, etc.
      (match (vhash-assoc (package-full-name package) name->package)
        ((_ . canon)
         ;; In general we want CANON, except if we're cross-compiling: CANON
         ;; uses explicit inputs, so it is "anchored" in the bootstrapped
         ;; process, with dependencies on things that cannot be
         ;; cross-compiled.
         (if (%current-target-system)
             package
             canon))
        (_ package)))))

\f
;;;
;;; GCC toolchain.
;;;

(define (gcc-toolchain gcc)
  "Return a complete toolchain for GCC."
  (package
    (name "gcc-toolchain")
    (version (package-version gcc))
    (source #f)
    (build-system trivial-build-system)
    (arguments
     '(#:modules ((guix build union))
       #:builder (begin
                   (use-modules (ice-9 match)
                                (srfi srfi-26)
                                (guix build union))

                   (let ((out (assoc-ref %outputs "out")))

                     (match %build-inputs
                       (((names . directories) ...)
                        (union-build out directories)))

                     ;; Remove the 'sh' and 'bash' binaries that come with
                     ;; libc to avoid polluting the user's profile (these are
                     ;; statically-linked binaries with no locale support and
                     ;; so on.)
                     (for-each (lambda (file)
                                 (delete-file (string-append out "/bin/" file)))
                               '("sh" "bash"))

                     (union-build (assoc-ref %outputs "debug")
                                  (list (assoc-ref %build-inputs
                                                   "libc-debug")))))))

    (native-search-paths (package-native-search-paths gcc))
    (search-paths (package-search-paths gcc))

    (license (package-license gcc))
    (synopsis "Complete GCC tool chain for C/C++ development")
    (description
     "This package provides a complete GCC tool chain for C/C++ development to
be installed in user profiles.  This includes GCC, as well as libc (headers
and binaries, plus debugging symbols in the 'debug' output), and Binutils.")
    (home-page "http://gcc.gnu.org/")
    (outputs '("out" "debug"))

    ;; The main raison d'être of this "meta-package" is (1) to conveniently
    ;; install everything that we need, and (2) to make sure ld-wrapper comes
    ;; before Binutils' ld in the user's profile.
    (inputs `(("gcc" ,gcc)
              ("ld-wrapper" ,(car (assoc-ref %final-inputs "ld-wrapper")))
              ("binutils" ,binutils-final)
              ("libc" ,glibc-final)
              ("libc-debug" ,glibc-final "debug")))))

(define-public gcc-toolchain-4.8
  (gcc-toolchain gcc-final))

(define-public gcc-toolchain-4.9
  (gcc-toolchain gcc-4.9))

(define-public gcc-toolchain-5
  (gcc-toolchain gcc-5))

;;; commencement.scm ends here