diff --git a/pkgs/development/libraries/libmad/default.nix b/pkgs/development/libraries/libmad/default.nix
index 883ad072c7b9..7739c3627ec9 100644
--- a/pkgs/development/libraries/libmad/default.nix
+++ b/pkgs/development/libraries/libmad/default.nix
@@ -8,7 +8,11 @@ stdenv.mkDerivation rec {
     sha256 = "bbfac3ed6bfbc2823d3775ebb931087371e142bb0e9bb1bee51a76a6e0078690";
   };
 
-  patches = [ ./001-mips_removal_h_constraint.patch ./pkgconfig.patch ];
+  patches = [ ./001-mips_removal_h_constraint.patch ./pkgconfig.patch ]
+  # optimize.diff is taken from https://projects.archlinux.org/svntogit/packages.git/tree/trunk/optimize.diff?h=packages/libmad
+  # It is included here in order to fix a build failure in Clang
+  # But it may be useful to fix other, currently unknown problems as well
+  ++ stdenv.lib.optional (stdenv.cc.cc.isClang or false) [ ./optimize.diff ];
 
   nativeBuildInputs = [ autoconf ];
 
@@ -22,6 +26,7 @@ stdenv.mkDerivation rec {
   meta = with stdenv.lib; {
     homepage    = http://sourceforge.net/projects/mad/;
     description = "A high-quality, fixed-point MPEG audio decoder supporting MPEG-1 and MPEG-2";
+    license     = licenses.gpl2;
     maintainers = with maintainers; [ lovek323 ];
     platforms   = platforms.unix;
   };
diff --git a/pkgs/development/libraries/libmad/optimize.diff b/pkgs/development/libraries/libmad/optimize.diff
new file mode 100644
index 000000000000..1418dc927073
--- /dev/null
+++ b/pkgs/development/libraries/libmad/optimize.diff
@@ -0,0 +1,77 @@
+Index: libmad-0.15.1b/configure.ac
+===================================================================
+--- libmad-0.15.1b.orig/configure.ac	2008-03-07 20:31:23.000000000 +0000
++++ libmad-0.15.1b/configure.ac	2008-03-07 20:34:26.000000000 +0000
+@@ -124,71 +124,7 @@
+ 
+ if test "$GCC" = yes
+ then
+-    if test -z "$arch"
+-    then
+-	case "$host" in
+-	    i386-*)           ;;
+-	    i?86-*)           arch="-march=i486" ;;
+-	    arm*-empeg-*)     arch="-march=armv4 -mtune=strongarm1100" ;;
+-	    armv4*-*)         arch="-march=armv4 -mtune=strongarm" ;;
+-	    powerpc-*)        ;;
+-	    mips*-agenda-*)   arch="-mcpu=vr4100" ;;
+-	    mips*-luxsonor-*) arch="-mips1 -mcpu=r3000 -Wa,-m4010" ;;
+-	esac
+-    fi
+-
+-    case "$optimize" in
+-	-O|"-O "*)
+-	    optimize="-O"
+-	    optimize="$optimize -fforce-mem"
+-	    optimize="$optimize -fforce-addr"
+-	    : #x optimize="$optimize -finline-functions"
+-	    : #- optimize="$optimize -fstrength-reduce"
+-	    optimize="$optimize -fthread-jumps"
+-	    optimize="$optimize -fcse-follow-jumps"
+-	    optimize="$optimize -fcse-skip-blocks"
+-	    : #x optimize="$optimize -frerun-cse-after-loop"
+-	    : #x optimize="$optimize -frerun-loop-opt"
+-	    : #x optimize="$optimize -fgcse"
+-	    optimize="$optimize -fexpensive-optimizations"
+-	    optimize="$optimize -fregmove"
+-	    : #* optimize="$optimize -fdelayed-branch"
+-	    : #x optimize="$optimize -fschedule-insns"
+-	    optimize="$optimize -fschedule-insns2"
+-	    : #? optimize="$optimize -ffunction-sections"
+-	    : #? optimize="$optimize -fcaller-saves"
+-	    : #> optimize="$optimize -funroll-loops"
+-	    : #> optimize="$optimize -funroll-all-loops"
+-	    : #x optimize="$optimize -fmove-all-movables"
+-	    : #x optimize="$optimize -freduce-all-givs"
+-	    : #? optimize="$optimize -fstrict-aliasing"
+-	    : #* optimize="$optimize -fstructure-noalias"
+-
+-	    case "$host" in
+-		arm*-*)
+-		    optimize="$optimize -fstrength-reduce"
+-		    ;;
+-		mips*-*)
+-		    optimize="$optimize -fstrength-reduce"
+-		    optimize="$optimize -finline-functions"
+-		    ;;
+-		i?86-*)
+-		    optimize="$optimize -fstrength-reduce"
+-		    ;;
+-		powerpc-apple-*)
+-		    # this triggers an internal compiler error with gcc2
+-		    : #optimize="$optimize -fstrength-reduce"
+-
+-		    # this is really only beneficial with gcc3
+-		    : #optimize="$optimize -finline-functions"
+-		    ;;
+-		*)
+-		    # this sometimes provokes bugs in gcc 2.95.2
+-		    : #optimize="$optimize -fstrength-reduce"
+-		    ;;
+-	    esac
+-	    ;;
+-    esac
++    optimize="-O2"
+ fi
+ 
+ case "$host" in