diff --git a/gnu/packages/base.scm b/gnu/packages/base.scm
index c83775d8ee..1005899490 100644
--- a/gnu/packages/base.scm
+++ b/gnu/packages/base.scm
@@ -1229,7 +1229,7 @@ (define-public glibc/hurd-headers
 (define-public tzdata
   (package
     (name "tzdata")
-    (version "2020a")
+    (version "2020b")
     (source (origin
              (method url-fetch)
              (uri (string-append
@@ -1237,7 +1237,7 @@ (define-public tzdata
                    version ".tar.gz"))
              (sha256
               (base32
-               "18lrp0zh8m931jjlrv8lvjas4ka5dfkzdbwnbw5lwd2dlbn62wal"))))
+               "02g88pbw82zr36x9dz5ib4sq6bfq253yx5hbhnfyhp143naky1cv"))))
     (build-system gnu-build-system)
     (arguments
      '(#:tests? #f
@@ -1287,7 +1287,7 @@ (define-public tzdata
                                 version ".tar.gz"))
                           (sha256
                            (base32
-                            "0sfnlqw1p93r7klny69rwr94fh22mz632h52phgzfgg01q9gfakx"))))))
+                            "1nj3zvqpy5lm6w365p9ynz4i5arq4fiy8ldq55v4z9p49nagivs7"))))))
     (home-page "https://www.iana.org/time-zones")
     (synopsis "Database of current and historical time zones")
     (description "The Time Zone Database (often called tz or zoneinfo)
diff --git a/gnu/packages/golang.scm b/gnu/packages/golang.scm
index 0f81a752e4..9fe3184371 100644
--- a/gnu/packages/golang.scm
+++ b/gnu/packages/golang.scm
@@ -20,6 +20,7 @@
 ;;; Copyright © 2020 Jakub Kądziołka <kuba@kadziolka.net>
 ;;; Copyright © 2020 Nicolas Goaziou <mail@nicolasgoaziou.com>
 ;;; Copyright © 2020 Ryan Prior <rprior@protonmail.com>
+;;; Copyright © 2020 Marius Bakke <marius@gnu.org>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -147,6 +148,11 @@ (define-public go-1.4
                   ("os/os_test.go" "(.+)(TestHostname.+)")
                   ("time/format_test.go" "(.+)(TestParseInSydney.+)")
 
+                  ;; XXX: This test fails with tzdata 2020b and newer.  Later
+                  ;; Go releases work fine, so just disable this for the
+                  ;; bootstrap Go.
+                  ("time/example_test.go" "(.+)(ExampleParseInLocation.+)")
+
                   ("os/exec/exec_test.go" "(.+)(TestEcho.+)")
                   ("os/exec/exec_test.go" "(.+)(TestCommandRelativeName.+)")
                   ("os/exec/exec_test.go" "(.+)(TestCatStdin.+)")