glibc: make NIX_CFLAGS_COMPILE a string

1 files changed, 4 insertions, 4 deletions

diff --git a/pkgs/development/libraries/glibc/default.nix b/pkgs/development/libraries/glibc/default.nix
index 98e579cb7a6..1a17595a1a3 100644
--- a/pkgs/development/libraries/glibc/default.nix
+++ b/pkgs/development/libraries/glibc/default.nix
@@ -48,21 +48,21 @@ callPackage ./common.nix { inherit stdenv; } {
     #      limit rebuilds by only disabling pie w/musl
       ++ stdenv.lib.optional stdenv.hostPlatform.isMusl "pie";
 
-    NIX_CFLAGS_COMPILE =
-      if !stdenv.hostPlatform.isMusl
+    NIX_CFLAGS_COMPILE = stdenv.lib.concatStringsSep " "
+      (if !stdenv.hostPlatform.isMusl
         # TODO: This (returning a string or `null`, instead of a list) is to
         #       not trigger a mass rebuild due to the introduction of the
         #       musl-specific flags below.
         #       At next change to non-musl glibc builds, remove this `then`
         #       and the above condition, instead keeping only the `else` below.
-        then (if withGd then gdCflags else null)
+        then (stdenv.lib.optionals withGd gdCflags)
         else
           (builtins.concatLists [
             (stdenv.lib.optionals withGd gdCflags)
             # Fix -Werror build failure when building glibc with musl with GCC >= 8, see:
             # https://github.com/NixOS/nixpkgs/pull/68244#issuecomment-544307798
             (stdenv.lib.optional stdenv.hostPlatform.isMusl "-Wno-error=attribute-alias")
-          ]);
+          ]));
 
     # When building glibc from bootstrap-tools, we need libgcc_s at RPATH for
     # any program we run, because the gcc will have been placed at a new