[bug#39918] [PATCH 1/2] gnu: avr-gcc: Update to 7.4.0.

[Arun Isaac <arunisaac@systemreboot.net>]

* gnu/packages/avr.scm (avr-gcc-7, avr-toolchain-7): New variables.
(avr-gcc-4.9, avr-gcc-5, avr-toolchain-4.9, avr-toolchain-5): Delete
variables.
(avr-libc)[arguments]: Remove custom fix-cpath phase.
---
 gnu/packages/avr.scm | 32 ++++++--------------------------
 1 file changed, 6 insertions(+), 26 deletions(-)

diff --git a/gnu/packages/avr.scm b/gnu/packages/avr.scm
index 608e487b93..8a964b9b17 100644
--- a/gnu/packages/avr.scm
+++ b/gnu/packages/avr.scm
@@ -4,6 +4,7 @@
 ;;; Copyright © 2016 David Thompson <davet@gnu.org>
 ;;; Copyright © 2016 Efraim Flashner <efraim@flashner.co.il>
 ;;; Copyright © 2018 Tobias Geerinckx-Rice <me@tobias.gr>
+;;; Copyright © 2020 Arun Isaac <arunisaac@systemreboot.net>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -40,8 +41,8 @@
     (inherit (cross-binutils "avr"))
     (name "avr-binutils")))
 
-(define-public avr-gcc-4.9
-  (let ((xgcc (cross-gcc "avr" #:xgcc gcc-4.9 #:xbinutils avr-binutils)))
+(define-public avr-gcc-7
+  (let ((xgcc (cross-gcc "avr" #:xgcc gcc-7 #:xbinutils avr-binutils)))
     (package
       (inherit xgcc)
       (name "avr-gcc")
@@ -78,18 +79,9 @@
               (variable "CROSS_LIBRARY_PATH")
               (files '("avr/lib")))))
       (native-inputs
-       `(("gcc" ,gcc-5)
+       `(("gcc" ,gcc-7)
          ,@(package-native-inputs xgcc))))))
 
-(define-public avr-gcc-5
-  (package
-    (inherit avr-gcc-4.9)
-    (version (package-version gcc-5))
-    (source (origin
-              (inherit (package-source gcc-5))
-              (patches (append (origin-patches (package-source gcc-5))
-                               (search-patches "gcc-cross-environment-variables.patch")))))))
-
 (define (avr-libc avr-gcc)
   (package
     (name "avr-libc")
@@ -104,18 +96,7 @@
     (build-system gnu-build-system)
     (arguments
      '(#:out-of-source? #t
-       #:configure-flags '("--host=avr")
-       #:phases
-       (modify-phases %standard-phases
-         (add-before 'unpack 'fix-cpath
-           (lambda _
-             ;; C_INCLUDE_PATH and CPATH pose issues for cross-building,
-             ;; leading to failures when building avr-libc on 64-bit systems.
-             ;; Simply unsetting them allows the build to succeed because it
-             ;; doesn't try to use any of the native system's headers.
-             (unsetenv "C_INCLUDE_PATH")
-             (unsetenv "CPATH")
-             #t)))))
+       #:configure-flags '("--host=avr")))
     (native-inputs `(("avr-binutils" ,avr-binutils)
                      ("avr-gcc" ,avr-gcc)))
     (home-page "https://www.nongnu.org/avr-libc/")
@@ -149,8 +130,7 @@ C++.")
       (home-page (package-home-page avr-libc))
       (license (package-license avr-gcc)))))
 
-(define-public avr-toolchain-4.9 (avr-toolchain avr-gcc-4.9))
-(define-public avr-toolchain-5 (avr-toolchain avr-gcc-5))
+(define-public avr-toolchain-7 (avr-toolchain avr-gcc-7))
 
 (define-public microscheme
   (package
-- 
2.25.1