libucontext: build the hand-written asm files with -Wa,--noexecstack

meson.build omits the flag the Makefile passes, giving every static consumer
(e.g. pkgsStatic.lix via capnproto) an executable stack. :)

Signed-off-by: Raito Bezarius <masterancpp@gmail.com>

pkgs/by-name/li/libucontext/package.nix

@@ -23,6 +23,11 @@ stdenv.mkDerivation (finalAttrs: {
     ninja
   ];
 
+  # Makefile builds the asm files with -Wa,--noexecstack, meson.build does not.
+  # If you do not pass it, you get PT_GNU_STACK=RWE on static consumers of the library.
+  # https://github.com/kaniini/libucontext/issues/83
+  env.NIX_CFLAGS_COMPILE = "-Wa,--noexecstack";
+
   passthru.updateScript = nix-update-script { };
 
   meta = {