Keep line number in cond_clause error (#9730)

Author: ericmj

lib/elixir/src/elixir_erl_pass.erl

@@ -126,7 +126,7 @@ translate({'cond', CondMeta, [[{do, Clauses}]]}, S) ->
       true -> Meta
     end,
 
-  Error = {{'.', Meta, [erlang, error]}, [], [cond_clause]},
+  Error = {{'.', Meta, [erlang, error]}, Meta, [cond_clause]},
   {Case, SC} = build_cond_clauses([H | T], Error, FirstMeta, S),
   translate(replace_case_meta(CondMeta, Case), SC);
 

lib/elixir/test/elixir/kernel/special_forms_test.exs

@@ -52,5 +52,20 @@ defmodule Kernel.SpecialFormsTest do
         :otherwise -> :also_good
       end
     end
+
+    def false_fun(), do: false
+
+    test "cond_clause error keeps line number in stacktrace" do
+      try do
+        cond do
+          false_fun() -> :ok
+        end
+      rescue
+        _ ->
+          assert [{Kernel.SpecialFormsTest, _, _, meta} | _] = __STACKTRACE__
+          assert meta[:file]
+          assert meta[:line]
+      end
+    end
   end
 end