diff --git a/pkgs/development/libraries/smpeg/default.nix b/pkgs/development/libraries/smpeg/default.nix
index 6803dfd76de9..f248d65e2ed6 100644
--- a/pkgs/development/libraries/smpeg/default.nix
+++ b/pkgs/development/libraries/smpeg/default.nix
@@ -10,9 +10,12 @@ stdenv.mkDerivation rec {
     sha256 = "0ynwn7ih5l2b1kpzpibns9bb9wzfjak7mgrb1ji0dkn2q5pv6lr0";
   };
 
-  enableParallelBuilding = true;
+  patches = [
+    ./format.patch
+    ./gcc6.patch
+  ];
 
-  hardeningDisable = [ "format" ];
+  enableParallelBuilding = true;
 
   buildInputs = [ SDL gtk2 mesa ];
 
diff --git a/pkgs/development/libraries/smpeg/format.patch b/pkgs/development/libraries/smpeg/format.patch
new file mode 100644
index 000000000000..8486dee5cda4
--- /dev/null
+++ b/pkgs/development/libraries/smpeg/format.patch
@@ -0,0 +1,11 @@
+--- a/plaympeg.c	2014-09-04 08:55:10.646132150 +0200
++++ b/plaympeg.c	2014-09-04 08:56:57.465210820 +0200
+@@ -262,7 +262,7 @@
+       answer[i] = c;
+     }
+     answer[i] = 0;
+-    fprintf(stderr, answer + 4);
++    fprintf(stderr, "%s", answer + 4);
+   }
+   while(answer[3] == '-');
+ 
diff --git a/pkgs/development/libraries/smpeg/gcc6.patch b/pkgs/development/libraries/smpeg/gcc6.patch
new file mode 100644
index 000000000000..165feb4428c2
--- /dev/null
+++ b/pkgs/development/libraries/smpeg/gcc6.patch
@@ -0,0 +1,33 @@
+--- a/audio/hufftable.cpp
++++ b/audio/hufftable.cpp
+@@ -9,6 +9,7 @@
+ #include "config.h"
+ #endif
+ 
++#include <climits>
+ #include "MPEGaudio.h"
+ 
+ static const unsigned int
+@@ -550,11 +551,11 @@ htd33[ 31][2]={{ 16,  1},{  8,  1},{  4,
+ 
+ const HUFFMANCODETABLE MPEGaudio::ht[HTN]=
+ {
+-  { 0, 0-1, 0-1, 0,  0, htd33},
++  { 0, UINT_MAX, UINT_MAX, 0,  0, htd33},
+   { 1, 2-1, 2-1, 0,  7,htd01},
+   { 2, 3-1, 3-1, 0, 17,htd02},
+   { 3, 3-1, 3-1, 0, 17,htd03},
+-  { 4, 0-1, 0-1, 0,  0, htd33},
++  { 4, UINT_MAX, UINT_MAX, 0,  0, htd33},
+   { 5, 4-1, 4-1, 0, 31,htd05},
+   { 6, 4-1, 4-1, 0, 31,htd06},
+   { 7, 6-1, 6-1, 0, 71,htd07},
+@@ -564,7 +565,7 @@ const HUFFMANCODETABLE MPEGaudio::ht[HTN
+   {11, 8-1, 8-1, 0,127,htd11},
+   {12, 8-1, 8-1, 0,127,htd12},
+   {13,16-1,16-1, 0,511,htd13},
+-  {14, 0-1, 0-1, 0,  0, htd33},
++  {14, UINT_MAX, UINT_MAX, 0,  0, htd33},
+   {15,16-1,16-1, 0,511,htd15},
+   {16,16-1,16-1, 1,511,htd16},
+   {17,16-1,16-1, 2,511,htd16},