From 5fed44311cce087b0f135412984de6aa766e707f Mon Sep 17 00:00:00 2001
From: Nick Gasson <nick@nickg.me.uk>
Date: Mon, 5 Feb 2024 21:56:32 +0000
Subject: [PATCH] Allow use of type alias in slice name. Fixes #845

---
 src/parse.c             |  2 +-
 test/parse/issue845.vhd | 15 +++++++++++++++
 test/test_parse.c       | 18 ++++++++++++++++++
 3 files changed, 34 insertions(+), 1 deletion(-)
 create mode 100644 test/parse/issue845.vhd

diff --git a/src/parse.c b/src/parse.c
index e50a99fb..8e3fa147 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -1543,7 +1543,7 @@ static bool is_range_expr(tree_t t)
    switch (tree_kind(t)) {
    case T_REF:
       if (tree_has_ref(t))
-         return is_type_decl(tree_ref(t));
+         return aliased_type_decl(tree_ref(t)) != NULL;
       else
          return !!(query_name(nametab, tree_ident(t), NULL) & N_TYPE);
 
diff --git a/test/parse/issue845.vhd b/test/parse/issue845.vhd
new file mode 100644
index 00000000..56050b46
--- /dev/null
+++ b/test/parse/issue845.vhd
@@ -0,0 +1,15 @@
+entity AliasRangeExample is
+end entity AliasRangeExample;
+
+architecture Bhv of AliasRangeExample is
+
+    signal A: bit_vector(31 downto 0);
+    signal B,C,D: bit_vector(7 downto 0);
+
+    subtype aRange is natural range 7 downto 0;
+    alias aRangeAlias is aRange;
+begin
+    B <= A(aRange); -- okay
+    C <= A(aRangeAlias'range); -- okay
+    D <= A(aRangeAlias); -- ** Error: invalid use of alias ARANGEALIAS
+end architecture;
diff --git a/test/test_parse.c b/test/test_parse.c
index 4fa54c07..73cf99c1 100644
--- a/test/test_parse.c
+++ b/test/test_parse.c
@@ -6116,6 +6116,23 @@ START_TEST(test_issue837)
 }
 END_TEST
 
+START_TEST(test_issue845)
+{
+   input_from_file(TESTDIR "/parse/issue845.vhd");
+
+   tree_t e = parse();
+   fail_if(e == NULL);
+   fail_unless(tree_kind(e) == T_ENTITY);
+   lib_put(lib_work(), e);
+
+   tree_t a = parse();
+   fail_if(a == NULL);
+   fail_unless(tree_kind(a) == T_ARCH);
+
+   fail_if_errors();
+}
+END_TEST
+
 Suite *get_parse_tests(void)
 {
    Suite *s = suite_create("parse");
@@ -6251,6 +6268,7 @@ Suite *get_parse_tests(void)
    tcase_add_test(tc_core, test_issue805);
    tcase_add_test(tc_core, test_visibility11);
    tcase_add_test(tc_core, test_issue837);
+   tcase_add_test(tc_core, test_issue845);
    suite_add_tcase(s, tc_core);
 
    return s;
-- 
2.39.2