From 5b272332fb00d520c60ec6bc959c9a29d832cdc3 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Sat, 25 Jan 2025 14:40:09 -0300
Subject: [PATCH] cgen: fix codegen for const fixed array initialization with
 another const as item (fix #23565) (#23572)

---
 vlib/v/gen/c/cgen.v                                    |  7 +++++--
 vlib/v/gen/c/consts_and_globals.v                      | 10 ++++++++++
 .../consts/const_fixed_array_with_var_item_test.v      |  7 +++++++
 3 files changed, 22 insertions(+), 2 deletions(-)
 create mode 100644 vlib/v/tests/consts/const_fixed_array_with_var_item_test.v

diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index cc75bdf57..29b032fde 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -6076,14 +6076,17 @@ fn (mut g Gen) check_expr_is_const(expr ast.Expr) bool {
 		ast.InfixExpr {
 			return g.check_expr_is_const(expr.left) && g.check_expr_is_const(expr.right)
 		}
-		ast.Ident, ast.StructInit, ast.EnumVal {
+		ast.Ident {
+			return expr.kind == .function || g.table.final_sym(expr.obj.typ).kind != .array_fixed
+		}
+		ast.StructInit, ast.EnumVal {
 			return true
 		}
 		ast.CastExpr {
 			return g.check_expr_is_const(expr.expr)
 		}
 		ast.PrefixExpr {
-			return g.check_expr_is_const(expr.right)
+			return expr.right is ast.Ident || g.check_expr_is_const(expr.right)
 		}
 		else {
 			return false
diff --git a/vlib/v/gen/c/consts_and_globals.v b/vlib/v/gen/c/consts_and_globals.v
index b6d6c4fca..bb4dc7a9f 100644
--- a/vlib/v/gen/c/consts_and_globals.v
+++ b/vlib/v/gen/c/consts_and_globals.v
@@ -367,6 +367,16 @@ fn (mut g Gen) const_decl_init_later_msvc_string_fixed_array(mod string, name st
 			elem_typ := g.styp(elem_expr.typ)
 			init.writeln(g.expr_string_surround('\tmemcpy(${cname}[${i}], (${elem_typ})',
 				elem_expr, ', sizeof(${elem_typ}));'))
+		} else if elem_expr is ast.Ident {
+			elem_typ := elem_expr.obj.typ
+			if g.table.final_sym(elem_typ).kind == .array_fixed {
+				elem_styp := g.styp(elem_expr.obj.typ)
+				init.writeln(g.expr_string_surround('\tmemcpy(${cname}[${i}], ', elem_expr,
+					', sizeof(${elem_styp}));'))
+			} else {
+				init.writeln(g.expr_string_surround('\t${cname}[${i}] = ', elem_expr,
+					';'))
+			}
 		} else {
 			init.writeln(g.expr_string_surround('\t${cname}[${i}] = ', elem_expr, ';'))
 		}
diff --git a/vlib/v/tests/consts/const_fixed_array_with_var_item_test.v b/vlib/v/tests/consts/const_fixed_array_with_var_item_test.v
new file mode 100644
index 000000000..f9bb8ac0b
--- /dev/null
+++ b/vlib/v/tests/consts/const_fixed_array_with_var_item_test.v
@@ -0,0 +1,7 @@
+const f = [u8(0), 1, 2]!
+
+const ff = [[u8(1), 2, 3]!, [u8(5), 4, 3]!, f]!
+
+fn test_main() {
+	assert ff == [[u8(1), 2, 3]!, [u8(5), 4, 3]!, [u8(0), 1, 2]!]!
+}
-- 
2.39.5