treewide: NIX_CFLAGS_COMPILE -> string

pkgs/development/libraries/gdbm/default.nix

@@ -4,9 +4,6 @@ stdenv.mkDerivation rec {
   pname = "gdbm";
   version = "1.18.1";
 
-  # FIXME: remove on update to > 1.18.1
-  NIX_CFLAGS_COMPILE = if stdenv.cc.isClang then "-Wno-error=return-type" else null;
-
   src = fetchurl {
     url = "mirror://gnu/gdbm/${pname}-${version}.tar.gz";
     sha256 = "1p4ibds6z3ccy65lkmd6lm7js0kwifvl53r0fd759fjxgr917rl6";

pkgs/development/libraries/glib/default.nix

@@ -118,7 +118,7 @@ stdenv.mkDerivation rec {
     "-Ddevbindir=${placeholder ''dev''}/bin"
   ];
 
-  NIX_CFLAGS_COMPILE = [
+  NIX_CFLAGS_COMPILE = toString [
     "-Wno-error=nonnull"
     # Default for release buildtype but passed manually because
     # we're using plain

pkgs/development/libraries/libglvnd/default.nix

@@ -39,13 +39,13 @@ stdenv.mkDerivation rec {
       --replace "-Xlinker --version-script=$(VERSION_SCRIPT)" "-Xlinker"
   '';
 
-  NIX_CFLAGS_COMPILE = [
+  NIX_CFLAGS_COMPILE = toString ([
     "-UDEFAULT_EGL_VENDOR_CONFIG_DIRS"
     # FHS paths are added so that non-NixOS applications can find vendor files.
     "-DDEFAULT_EGL_VENDOR_CONFIG_DIRS=\"${addOpenGLRunpath.driverLink}/share/glvnd/egl_vendor.d:/etc/glvnd/egl_vendor.d:/usr/share/glvnd/egl_vendor.d\""
 
     "-Wno-error=array-bounds"
-  ] ++ lib.optional stdenv.cc.isClang "-Wno-error";
+  ] ++ lib.optional stdenv.cc.isClang "-Wno-error");
 
   # Indirectly: https://bugs.freedesktop.org/show_bug.cgi?id=35268
   configureFlags  = stdenv.lib.optional stdenv.hostPlatform.isMusl "--disable-tls";

pkgs/development/libraries/libpfm/default.nix

@@ -16,7 +16,7 @@ stdenv.mkDerivation (rec {
     "SYS=${stdenv.hostPlatform.uname.system}"
   ];
 
-  NIX_CFLAGS_COMPILE = [ "-Wno-error" ];
+  NIX_CFLAGS_COMPILE = "-Wno-error";
 
   meta = with stdenv.lib; {
     description = "Helper library to program the performance monitoring events";

pkgs/development/libraries/libvdpau/default.nix

@@ -19,7 +19,7 @@ stdenv.mkDerivation rec {
   configureFlags = stdenv.lib.optional stdenv.isLinux
     "--with-module-dir=${mesa.drivers.driverLink}/lib/vdpau";
 
-  NIX_LDFLAGS = if stdenv.isDarwin then "-lX11" else null;
+  NIX_LDFLAGS = stdenv.lib.optionalString stdenv.isDarwin "-lX11";
 
   installFlags = [ "moduledir=$(out)/lib/vdpau" ];
 

pkgs/development/libraries/openal-soft/default.nix

@@ -35,9 +35,9 @@ stdenv.mkDerivation rec {
     ++ optional pulseSupport libpulseaudio
     ++ optionals stdenv.isDarwin [ CoreServices AudioUnit AudioToolbox ];
 
-  NIX_LDFLAGS = []
+  NIX_LDFLAGS = toString ([]
     ++ optional alsaSupport "-lasound"
-    ++ optional pulseSupport "-lpulse";
+    ++ optional pulseSupport "-lpulse");
 
   meta = {
     description = "OpenAL alternative";

pkgs/development/libraries/sqlite/default.nix

@@ -25,7 +25,7 @@ stdenv.mkDerivation rec {
 
   configureFlags = [ "--enable-threadsafe" ] ++ optional interactive "--enable-readline";
 
-  NIX_CFLAGS_COMPILE = [
+  NIX_CFLAGS_COMPILE = toString [
     "-DSQLITE_ENABLE_COLUMN_METADATA"
     "-DSQLITE_ENABLE_DBSTAT_VTAB"
     "-DSQLITE_ENABLE_JSON1"