gdbm: avoid a warning on Darwin

This is just to minimize rebuilds.  The actual bugfix doesn't seem to
hurry, as the function has been returning void until now, so if the int
returned isn't a meaningful value in some cases, nothing should happen
yet.

1 files changed, 2 insertions, 0 deletions

diff --git a/pkgs/development/libraries/gdbm/default.nix b/pkgs/development/libraries/gdbm/default.nix
index ecab75fb0ea9..bbebcca6e2f0 100644
--- a/pkgs/development/libraries/gdbm/default.nix
+++ b/pkgs/development/libraries/gdbm/default.nix
@@ -2,6 +2,8 @@
 
 stdenv.mkDerivation rec {
   name = "gdbm-1.17";
+  # FIXME: remove on update to > 1.17
+  NIX_CFLAGS_COMPILE = if stdenv.cc.isClang then "-Wno-error=return-type" else null;
 
   src = fetchurl {
     url = "mirror://gnu/gdbm/${name}.tar.gz";