diff --git a/glpk-4.55.tar.gz b/glpk-4.55.tar.gz
deleted file mode 100644
index df7b26b..0000000
--- a/glpk-4.55.tar.gz
+++ /dev/null
@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:37090d7f16796ec1034496e182a39d5cc8bb7c9fb5dc48a38b13d620bf2b1de7
-size 3424345
diff --git a/glpk-4.55.tar.gz.sig b/glpk-4.55.tar.gz.sig
deleted file mode 100644
index 96fa1aa..0000000
Binary files a/glpk-4.55.tar.gz.sig and /dev/null differ
diff --git a/glpk-4.56.tar.gz b/glpk-4.56.tar.gz
new file mode 100644
index 0000000..7aef83c
--- /dev/null
+++ b/glpk-4.56.tar.gz
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:1085561013bf86c4c56ca0ed52150b4e5b653562043104ee77c0de8d4d8fdf6b
+size 4016267
diff --git a/glpk-4.56.tar.gz.sig b/glpk-4.56.tar.gz.sig
new file mode 100644
index 0000000..8f54f4d
Binary files /dev/null and b/glpk-4.56.tar.gz.sig differ
diff --git a/glpk.changes b/glpk.changes
index ef776d0..39cb92f 100644
--- a/glpk.changes
+++ b/glpk.changes
@@ -1,3 +1,18 @@
+-------------------------------------------------------------------
+Fri Oct  2 12:19:02 UTC 2015 - mpluskal@suse.com
+
+- Update to 4.56
+  * A new, more efficient and more robust implementation of the 
+    primal simplex method was included in the package. This new 
+    implementation replaces the old one, which was removed.
+  * A bug was fixed in a basis factorization routine. (The bug
+    appeared if the basis matrix was structurally singular having
+    duplicate row and/or column singletons.) Thanks to Martin Jacob
+  * Scripts to build GLPK with Microsoft Visual Studio 2015 were
+    added. Thanks to Xypron <xypron.glpk@gmx.de> for contribution
+    and testing.
+- Cleanup spec file with spec-clener
+
 -------------------------------------------------------------------
 Wed Nov 12 17:33:27 UTC 2014 - dmitry_r@opensuse.org
 
diff --git a/glpk.keyring b/glpk.keyring
index 7bf9957..46f2f4e 100644
--- a/glpk.keyring
+++ b/glpk.keyring
@@ -1,9 +1,5 @@
-pub   1024D/5981E818 2003-07-15
-uid                  Andrew Makhorin <mao@mai2.rcnet.ru>
-sub   1024g/5676121E 2003-07-15
-
 -----BEGIN PGP PUBLIC KEY BLOCK-----
-Version: GnuPG v2.0.19 (GNU/Linux)
+Version: GnuPG v2
 
 mQGiBD8UdT8RBAC6yWYxoa1b7U973J0jBuQpgZnhXlGJJpMZgAW9efDBD17vhkJm
 hPVOQBKRUeOOLcW3/a7NMoNLMdmF1Rgz1FPVy3RgBDsYj4Sp4RBCsX/o0xXh+jxe
@@ -14,15 +10,17 @@ IxN3LaK600BgAbwSd1bomRqWNlczAM7469VvGG9ASpCBveUUrqwerHZcUbvngL62
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+=bou8
 -----END PGP PUBLIC KEY BLOCK-----
diff --git a/glpk.spec b/glpk.spec
index d4cb6ef..5a687ca 100644
--- a/glpk.spec
+++ b/glpk.spec
@@ -1,7 +1,7 @@
 #
 # spec file for package glpk
 #
-# Copyright (c) 2014 SUSE LINUX Products GmbH, Nuernberg, Germany.
+# Copyright (c) 2015 SUSE LINUX GmbH, Nuernberg, Germany.
 #
 # All modifications and additions to the file contributed by third parties
 # remain the property of their copyright owners, unless otherwise agreed
@@ -18,16 +18,15 @@
 
 %define lname   libglpk36
 Name:           glpk
-Version:        4.55
+Version:        4.56
 Release:        0
 Summary:        GNU Linear Programming Kit
 License:        GPL-3.0
 Group:          Productivity/Scientific/Math
 Url:            http://www.gnu.org/software/glpk/glpk.html
-#DL-URL:        http://ftp.gnu.org/gnu/glpk/
-Source:         http://ftp.gnu.org/gnu/glpk/%{name}-%{version}.tar.gz
-Source2:        http://ftp.gnu.org/gnu/glpk/%{name}-%{version}.tar.gz.sig
-Source3:        %{name}.keyring
+Source0:        http://ftp.gnu.org/gnu/glpk/%{name}-%{version}.tar.gz
+Source1:        http://ftp.gnu.org/gnu/glpk/%{name}-%{version}.tar.gz.sig
+Source2:        %{name}.keyring
 BuildRequires:  ghostscript
 BuildRequires:  texlive
 BuildRoot:      %{_tmppath}/%{name}-%{version}-build
@@ -73,12 +72,12 @@ is a set of routines written in ANSI C and organized in the form of a
 callable library.
 
 %prep
-%{?gpg_verify: %gpg_verify %{SOURCE2}}
 %setup -q
 
 %build
 export CFLAGS="%{optflags} -fno-strict-aliasing"
-%configure --disable-static
+%configure \
+  --disable-static
 make %{?_smp_mflags}
 
 %install
@@ -91,7 +90,7 @@ cp doc/{*.txt,*.pdf} %{buildroot}%{_docdir}/%{name}/doc
 cp {AUTHORS,ChangeLog,COPYING,NEWS,README} %{buildroot}%{_docdir}/%{name}
 
 %check
-make check
+make %{?_smp_mflags} check
 
 %post -n %{lname} -p /sbin/ldconfig