gcc-lua-cdecl-strip-unsupported-attributes.patch

diff --git i/gcc/cdecl.lua w/gcc/cdecl.lua
index ed9e664..a96f284 100644
--- i/gcc/cdecl.lua
+++ w/gcc/cdecl.lua
@@ -14,30 +14,49 @@ local concat, insert, remove = table.concat, table.insert, table.remove
 -- Forward declaration.
 local format_node_class
 
+local luajit_ffi_supported_attributes = {
+    aligned     = true,
+    cdecl       = true,
+    fastcall    = true,
+    mode        = true,
+    packed      = true,
+    stdcall     = true,
+    thiscall    = true,
+    vector_size = true,
+}
+
 -- GCC C extension: Format declaration or type attributes.
 local function format_attributes(node, result, last)
   local attr = node:attributes()
   if attr and attr ~= last then
-    local pos = #result + 1
+    local partial = {}
     while true do
-      local partial = {}
-      insert(partial, attr:purpose():value())
+      local purpose = attr:purpose():value()
       local value = attr:value()
+      if not luajit_ffi_supported_attributes[purpose] then
+        goto continue
+      end
+      if #partial > 0 then
+        insert(partial, ", ")
+      end
+      insert(partial, purpose)
       if value then
-        local value = value:value()
+        value = value:value()
         insert(partial, "(")
         if value:code() == "string_cst" then insert(partial, [["]]) end
         insert(partial, value:value())
         if value:code() == "string_cst" then insert(partial, [["]]) end
         insert(partial, ")")
       end
+      ::continue::
       attr = attr:chain()
-      insert(result, pos, concat(partial))
       if not attr or attr == last then break end
-      insert(result, pos, ", ")
     end
-    insert(result, pos, " __attribute__((")
-    insert(result, "))")
+    if #partial > 0 then
+      insert(result, " __attribute__((")
+      insert(result, table.concat(partial))
+      insert(result, "))")
+    end
   end
 end