patch 8.2.0504: Vim9: leaking scope memory when compilation fails

Problem:    Vim9: leaking scope memory when compilation fails.
Solution:   Cleanup the scope list.

Author: brammool

src/version.c

@@ -738,6 +738,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    504,
 /**/
     503,
 /**/

src/vim9compile.c

@@ -3995,6 +3995,18 @@ compile_fill_jump_to_end(endlabel_T **el, cctx_T *cctx)
     }
 }
 
+    static void
+compile_free_jump_to_end(endlabel_T **el)
+{
+    while (*el != NULL)
+    {
+	endlabel_T  *cur = (*el);
+
+	*el = cur->el_next;
+	vim_free(cur);
+    }
+}
+
 /*
  * Create a new scope and set up the generic items.
  */
@@ -4026,6 +4038,20 @@ drop_scope(cctx_T *cctx)
 	return;
     }
     cctx->ctx_scope = scope->se_outer;
+    switch (scope->se_type)
+    {
+	case IF_SCOPE:
+	    compile_free_jump_to_end(&scope->se_u.se_if.is_end_label); break;
+	case FOR_SCOPE:
+	    compile_free_jump_to_end(&scope->se_u.se_for.fs_end_label); break;
+	case WHILE_SCOPE:
+	    compile_free_jump_to_end(&scope->se_u.se_while.ws_end_label); break;
+	case TRY_SCOPE:
+	    compile_free_jump_to_end(&scope->se_u.se_try.ts_end_label); break;
+	case NO_SCOPE:
+	case BLOCK_SCOPE:
+	    break;
+    }
     vim_free(scope);
 }
 
@@ -5519,6 +5545,9 @@ compile_def_function(ufunc_T *ufunc, int set_return_type)
 	if (!dfunc->df_deleted)
 	    --def_functions.ga_len;
 
+	while (cctx.ctx_scope != NULL)
+	    drop_scope(&cctx);
+
 	// Don't execute this function body.
 	ga_clear_strings(&ufunc->uf_lines);