From 7c82effc8c165c6d6cf0a1a7a9cdeb79f4200f0b Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Mon, 27 Aug 2018 14:39:58 -0400
Subject: [PATCH] stdenv: Deprecate non-list configureFlags

At some point it would be nice to remove suppport for this altogether.
---
 pkgs/stdenv/generic/make-derivation.nix | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/pkgs/stdenv/generic/make-derivation.nix b/pkgs/stdenv/generic/make-derivation.nix
index 8af6d0e040085..f3c58a0a9c259 100644
--- a/pkgs/stdenv/generic/make-derivation.nix
+++ b/pkgs/stdenv/generic/make-derivation.nix
@@ -209,8 +209,12 @@ rec {
 
           # This parameter is sometimes a string, sometimes null, and sometimes a list, yuck
           configureFlags = let inherit (lib) optional elem; in
-            (/**/ if lib.isString configureFlags then [configureFlags]
-             else if configureFlags == null      then []
+            (/**/ if lib.isString configureFlags then builtins.trace
+               "String `configureFlags` is deprecated since 18.09. Please use a list of flags, each a string."
+               [configureFlags]
+             else if configureFlags == null then builtins.trace
+               "Null `configureFlags` is deprecated since 18.09. Please use the empty list, `[]`"
+               []
              else                                     configureFlags)
             ++ optional (elem "build"  configurePlatforms) "--build=${stdenv.buildPlatform.config}"
             ++ optional (elem "host"   configurePlatforms) "--host=${stdenv.hostPlatform.config}"