From 91a25fb143ad0e2e20e8ddadea0c0610849adf92 Mon Sep 17 00:00:00 2001
From: Giacomo Leidi <address@hidden>
Date: Tue, 12 Nov 2019 00:24:49 +0100
Subject: [PATCH] gnu: boost: Build with python3.

* gnu/packages/boost.scm (boost):
[arguments]: Parameterize python version.
[native-inputs]: Use python3.
---
 gnu/packages/boost.scm | 41 +++++++++++++++++++++++++++++------------
 1 file changed, 29 insertions(+), 12 deletions(-)

diff --git a/gnu/packages/boost.scm b/gnu/packages/boost.scm
index a2253a9efc..389fd1fdb6 100644
--- a/gnu/packages/boost.scm
+++ b/gnu/packages/boost.scm
@@ -62,10 +62,13 @@
               ("zlib" ,zlib)))
     (native-inputs
      `(("perl" ,perl)
-       ("python" ,python-2)
+       ("python" ,python)
        ("tcsh" ,tcsh)))
     (arguments
-     `(#:tests? #f
+     `(#:modules ((guix build gnu-build-system)
+                  (guix build utils)
+                  (srfi srfi-1))
+       #:tests? #f
        #:make-flags
        (list "threading=multi" "link=shared"
 
@@ -83,6 +86,9 @@
          (replace 'configure
            (lambda* (#:key inputs outputs #:allow-other-keys)
              (let ((icu (assoc-ref inputs "icu4c"))
+                   (python (assoc-ref inputs "python"))
+                   (python-version
+                    (take (string-split ,(package-version python) #\.) 2))
                    (out (assoc-ref outputs "out")))
                (substitute* '("libs/config/configure"
                               "libs/spirit/classic/phoenix/test/runtest.sh"
@@ -94,11 +100,19 @@
                (setenv "SHELL" (which "sh"))
                (setenv "CONFIG_SHELL" (which "sh"))
 
+               (substitute* "tools/build/src/tools/python.jam"
+                 (("include/python\\$\\(version\\)")
+                  "include/python$(version)m"))
+
                (invoke "./bootstrap.sh"
                        (string-append "--prefix=" out)
-                       ;; Auto-detection looks for ICU only in traditional
-                       ;; install locations.
+                       ;; Auto-detection looks for dependencies only
+                       ;; in traditional install locations.
                        (string-append "--with-icu=" icu)
+                       (string-append "--with-python=" python "/bin/python3")
+                       (string-append "--with-python-root=" python)
+                       (string-append "--with-python-version="
+                                      (string-join python-version "."))
                        "--with-toolset=gcc"))))
          (replace 'build
            (lambda* (#:key make-flags #:allow-other-keys)
@@ -109,15 +123,18 @@
            (lambda* (#:key make-flags #:allow-other-keys)
              (apply invoke "./b2" "install" make-flags)))
          (add-after 'install 'provide-libboost_python
-           (lambda* (#:key outputs #:allow-other-keys)
-             (let ((out (assoc-ref outputs "out")))
-               ;; Boost can build support for both Python 2 and Python 3 since
-               ;; version 1.67.0, and suffixes each library with the Python
-               ;; version.  Many consumers only check for libboost_python
-               ;; however, so we provide it here as suggested in
-               ;; <https://github.com/boostorg/python/issues/203>.
+           (lambda* (#:key inputs outputs #:allow-other-keys)
+             (let* ((out (assoc-ref outputs "out"))
+                    (python (assoc-ref inputs "python"))
+                    (python-version
+                     (take (string-split ,(package-version python) #\.) 2))
+                    (libboost.so (string-append "libboost_python"
+                                                (string-join python-version "")
+                                                ".so")))
                (with-directory-excursion (string-append out "/lib")
-                 (symlink "libboost_python27.so" "libboost_python.so"))
+                 (symlink libboost.so "libboost_python.so")
+                 ;; Some packages also look for libboost_python3.so
+                 (symlink libboost.so "libboost_python3.so"))
                #t))))))
 
     (home-page "https://www.boost.org")
-- 
2.24.0