diff --git a/pkgs/applications/graphics/icon-library/default.nix b/pkgs/applications/graphics/icon-library/default.nix
index 2f4aae6dc261..8b2347f43818 100644
--- a/pkgs/applications/graphics/icon-library/default.nix
+++ b/pkgs/applications/graphics/icon-library/default.nix
@@ -2,12 +2,14 @@
 , stdenv
 , fetchurl
 , wrapGAppsHook4
+, buildPackages
 , cargo
 , desktop-file-utils
 , meson
 , ninja
 , pkg-config
 , rustc
+, gettext
 , gdk-pixbuf
 , glib
 , gtk4
@@ -25,6 +27,14 @@ stdenv.mkDerivation rec {
     hash = "sha256-nWGTYoSa0/fxnD0Mb2132LkeB1oa/gj/oIXBbI+FDw8=";
   };
 
+  env = lib.optionalAttrs stdenv.isDarwin {
+    # Set the location to gettext to ensure the nixpkgs one on Darwin instead of the vendored one.
+    # The vendored gettext does not build with clang 16.
+    GETTEXT_BIN_DIR = "${lib.getBin buildPackages.gettext}/bin";
+    GETTEXT_INCLUDE_DIR = "${lib.getDev gettext}/include";
+    GETTEXT_LIB_DIR = "${lib.getLib gettext}/lib";
+  };
+
   nativeBuildInputs = [
     cargo
     desktop-file-utils
diff --git a/pkgs/development/libraries/gtksourceview/5.x.nix b/pkgs/development/libraries/gtksourceview/5.x.nix
index d4ac1e9bb09f..f1a12eb0de12 100644
--- a/pkgs/development/libraries/gtksourceview/5.x.nix
+++ b/pkgs/development/libraries/gtksourceview/5.x.nix
@@ -40,6 +40,9 @@ stdenv.mkDerivation (finalAttrs: {
     ./4.x-nix_share_path.patch
   ];
 
+  # The 10.12 SDK used by x86_64-darwin requires defining `_POSIX_C_SOURCE` to use `strnlen`.
+  env.NIX_CFLAGS_COMPILE = lib.optionalString (stdenv.isDarwin && stdenv.isx86_64) "-D_POSIX_C_SOURCE=200809L";
+
   nativeBuildInputs = [
     meson
     ninja
@@ -113,7 +116,5 @@ stdenv.mkDerivation (finalAttrs: {
     platforms = platforms.unix;
     license = licenses.lgpl21Plus;
     maintainers = teams.gnome.members;
-    # https://hydra.nixos.org/build/258191535/nixlog/1
-    broken = stdenv.isDarwin && stdenv.isx86_64;
   };
 })