diff --git a/pkgs/development/libraries/glibc-2.11/builder.sh b/pkgs/development/libraries/glibc-2.12/builder.sh
similarity index 100%
rename from pkgs/development/libraries/glibc-2.11/builder.sh
rename to pkgs/development/libraries/glibc-2.12/builder.sh
diff --git a/pkgs/development/libraries/glibc-2.11/common.nix b/pkgs/development/libraries/glibc-2.12/common.nix
similarity index 96%
rename from pkgs/development/libraries/glibc-2.11/common.nix
rename to pkgs/development/libraries/glibc-2.12/common.nix
index b2dd01690df..d35062f0957 100644
--- a/pkgs/development/libraries/glibc-2.11/common.nix
+++ b/pkgs/development/libraries/glibc-2.12/common.nix
@@ -11,7 +11,7 @@ cross :
 
 let
   # For GNU/Hurd, see below.
-  version = if hurdHeaders != null then "20100512" else "2.11.2";
+  version = if hurdHeaders != null then "20100512" else "2.12.1";
 in
 
 assert (cross != null) -> (gccCross != null);
@@ -128,11 +128,11 @@ stdenv.mkDerivation ({
     }
     else fetchurl {
       url = "mirror://gnu/glibc/glibc-${version}.tar.bz2";
-      sha256 = "04w74879psq961cas1amidkg8fc1h6r9yj3plfr33v9y6vp7db62";
+      sha256 = "01vlr473skl08xpcjz0b4lw23lsnskf5kx9s8nxwa4mwa9f137vm";
     };
 
   srcPorts = fetchurl {
-    url = "mirror://gnu/glibc/glibc-ports-2.11.tar.bz2";
+    url = "mirror://gnu/glibc/glibc-ports-2.11.tar.bz2"; # FIXME: 2.12.1 unavailable.
     sha256 = "12b53f5k4gcr8rr1kg2ycf2701rygqsyf9r8gz4j3l9flaqi5liq";
   };
 
diff --git a/pkgs/development/libraries/glibc-2.11/default.nix b/pkgs/development/libraries/glibc-2.12/default.nix
similarity index 100%
rename from pkgs/development/libraries/glibc-2.11/default.nix
rename to pkgs/development/libraries/glibc-2.12/default.nix
diff --git a/pkgs/development/libraries/glibc-2.11/gnu89-inline.patch b/pkgs/development/libraries/glibc-2.12/gnu89-inline.patch
similarity index 100%
rename from pkgs/development/libraries/glibc-2.11/gnu89-inline.patch
rename to pkgs/development/libraries/glibc-2.12/gnu89-inline.patch
diff --git a/pkgs/development/libraries/glibc-2.11/info.nix b/pkgs/development/libraries/glibc-2.12/info.nix
similarity index 100%
rename from pkgs/development/libraries/glibc-2.11/info.nix
rename to pkgs/development/libraries/glibc-2.12/info.nix
diff --git a/pkgs/development/libraries/glibc-2.11/locales-builder.sh b/pkgs/development/libraries/glibc-2.12/locales-builder.sh
similarity index 100%
rename from pkgs/development/libraries/glibc-2.11/locales-builder.sh
rename to pkgs/development/libraries/glibc-2.12/locales-builder.sh
diff --git a/pkgs/development/libraries/glibc-2.11/locales.nix b/pkgs/development/libraries/glibc-2.12/locales.nix
similarity index 100%
rename from pkgs/development/libraries/glibc-2.11/locales.nix
rename to pkgs/development/libraries/glibc-2.12/locales.nix
diff --git a/pkgs/development/libraries/glibc-2.11/mod_nano.patch b/pkgs/development/libraries/glibc-2.12/mod_nano.patch
similarity index 100%
rename from pkgs/development/libraries/glibc-2.11/mod_nano.patch
rename to pkgs/development/libraries/glibc-2.12/mod_nano.patch
diff --git a/pkgs/development/libraries/glibc-2.11/nix-locale-archive.patch b/pkgs/development/libraries/glibc-2.12/nix-locale-archive.patch
similarity index 100%
rename from pkgs/development/libraries/glibc-2.11/nix-locale-archive.patch
rename to pkgs/development/libraries/glibc-2.12/nix-locale-archive.patch
diff --git a/pkgs/development/libraries/glibc-2.11/nss-skip-unavail.patch b/pkgs/development/libraries/glibc-2.12/nss-skip-unavail.patch
similarity index 100%
rename from pkgs/development/libraries/glibc-2.11/nss-skip-unavail.patch
rename to pkgs/development/libraries/glibc-2.12/nss-skip-unavail.patch
diff --git a/pkgs/development/libraries/glibc-2.11/rpcgen-path.patch b/pkgs/development/libraries/glibc-2.12/rpcgen-path.patch
similarity index 100%
rename from pkgs/development/libraries/glibc-2.11/rpcgen-path.patch
rename to pkgs/development/libraries/glibc-2.12/rpcgen-path.patch
diff --git a/pkgs/development/libraries/glibc-2.11/stack-protector-link.patch b/pkgs/development/libraries/glibc-2.12/stack-protector-link.patch
similarity index 100%
rename from pkgs/development/libraries/glibc-2.11/stack-protector-link.patch
rename to pkgs/development/libraries/glibc-2.12/stack-protector-link.patch
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 4c8a1da089e..a01fa79511e 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -2821,7 +2821,7 @@ let
 
   glfw = callPackage ../development/libraries/glfw { };
 
-  glibc = glibc211;
+  glibc = glibc212;
 
   glibc25 = callPackage ../development/libraries/glibc-2.5 {
     kernelHeaders = linuxHeaders;
@@ -2845,7 +2845,7 @@ let
     installLocales = getPkgConfig "glibc" "locales" false;
   });
 
-  glibc211 = callPackage ../development/libraries/glibc-2.11 {
+  glibc212 = callPackage ../development/libraries/glibc-2.12 {
     kernelHeaders = linuxHeaders;
     installLocales = getPkgConfig "glibc" "locales" false;
     machHeaders = null;
@@ -2853,7 +2853,7 @@ let
     gccCross = null;
   };
 
-  glibc211Cross = forceBuildDrv (makeOverridable (import ../development/libraries/glibc-2.11)
+  glibc212Cross = forceBuildDrv (makeOverridable (import ../development/libraries/glibc-2.12)
     (let crossGNU = (crossSystem != null && crossSystem.config == "i586-pc-gnu");
      in ({
        inherit stdenv fetchurl;
@@ -2868,7 +2868,7 @@ let
       then { inherit machHeaders hurdHeaders mig fetchgit; }
       else { }))));
 
-  glibcCross = glibc211Cross;
+  glibcCross = glibc212Cross;
 
   # We can choose:
   libcCrossChooser = name : if (name == "glibc") then glibcCross