diff --git a/pkgs/tools/graphics/zbar/default.nix b/pkgs/tools/graphics/zbar/default.nix
index cb5ea25211c..6423a84badc 100644
--- a/pkgs/tools/graphics/zbar/default.nix
+++ b/pkgs/tools/graphics/zbar/default.nix
@@ -50,6 +50,9 @@ stdenv.mkDerivation rec {
     qtx11extras
   ];
 
+  # Disable assertions which include -dev QtBase file paths.
+  NIX_CFLAGS_COMPILE = [ "-DQT_NO_DEBUG" ];
+
   configureFlags = [
     "--without-python"
   ] ++ (if enableDbus then [