From d5dba2d4c61290a33e2f1ab060578b63acdc80ef Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Tue, 2 Jan 2024 12:40:23 -0300
Subject: [PATCH] cgen: fix dumping for a pointer to a fixed array
 initialization with prefixexpr & (fix #20344)

---
 vlib/v/gen/c/array.v                |  6 ++++--
 vlib/v/gen/c/dumpexpr.v             |  9 +++++++--
 vlib/v/tests/array_fixed_ptr_test.v | 11 +++++++++++
 3 files changed, 22 insertions(+), 4 deletions(-)
 create mode 100644 vlib/v/tests/array_fixed_ptr_test.v

diff --git a/vlib/v/gen/c/array.v b/vlib/v/gen/c/array.v
index e6cf440f74..50d9e3d61c 100644
--- a/vlib/v/gen/c/array.v
+++ b/vlib/v/gen/c/array.v
@@ -24,7 +24,7 @@ fn (mut g Gen) array_init(node ast.ArrayInit, var_name string) {
 	}
 	len := node.exprs.len
 	if array_type.unaliased_sym.kind == .array_fixed {
-		g.fixed_array_init(node, array_type, var_name)
+		g.fixed_array_init(node, array_type, var_name, is_amp)
 		if is_amp {
 			g.write(')')
 		}
@@ -79,7 +79,7 @@ fn (mut g Gen) array_init(node ast.ArrayInit, var_name string) {
 	}
 }
 
-fn (mut g Gen) fixed_array_init(node ast.ArrayInit, array_type Type, var_name string) {
+fn (mut g Gen) fixed_array_init(node ast.ArrayInit, array_type Type, var_name string, is_amp bool) {
 	prev_inside_lambda := g.inside_lambda
 	g.inside_lambda = true
 	defer {
@@ -177,6 +177,8 @@ fn (mut g Gen) fixed_array_init(node ast.ArrayInit, array_type Type, var_name st
 				g.write(', ')
 			}
 		}
+	} else if is_amp {
+		g.write('0')
 	} else {
 		elem_sym := g.table.final_sym(node.elem_type)
 		if elem_sym.kind == .map {
diff --git a/vlib/v/gen/c/dumpexpr.v b/vlib/v/gen/c/dumpexpr.v
index 9f01ca2e1d..c8f9407db9 100644
--- a/vlib/v/gen/c/dumpexpr.v
+++ b/vlib/v/gen/c/dumpexpr.v
@@ -210,8 +210,13 @@ fn (mut g Gen) dump_expr_definitions() {
 		surrounder.builder_write_afters(mut dump_fns)
 		if is_fixed_arr_ret {
 			tmp_var := g.new_tmp_var()
-			dump_fns.writeln('\t${str_dumparg_ret_type} ${tmp_var} = {0};')
-			dump_fns.writeln('\tmemcpy(${tmp_var}.ret_arr, dump_arg, sizeof(${str_dumparg_type}));')
+			if typ.is_ptr() {
+				dump_fns.writeln('\t${str_dumparg_ret_type} ${tmp_var} = HEAP(${g.typ(typ.set_nr_muls(0))}, {0});')
+				dump_fns.writeln('\tmemcpy(${tmp_var}->ret_arr, dump_arg, sizeof(${str_dumparg_type}));')
+			} else {
+				dump_fns.writeln('\t${str_dumparg_ret_type} ${tmp_var} = {0};')
+				dump_fns.writeln('\tmemcpy(${tmp_var}.ret_arr, dump_arg, sizeof(${str_dumparg_type}));')
+			}
 			dump_fns.writeln('\treturn ${tmp_var};')
 		} else {
 			dump_fns.writeln('\treturn dump_arg;')
diff --git a/vlib/v/tests/array_fixed_ptr_test.v b/vlib/v/tests/array_fixed_ptr_test.v
new file mode 100644
index 0000000000..0e02b4002e
--- /dev/null
+++ b/vlib/v/tests/array_fixed_ptr_test.v
@@ -0,0 +1,11 @@
+fn test_main() {
+	a := &[2]u8{}
+	dump(a)
+	assert a.len == 2
+}
+
+fn test_empty() {
+	_ := &[2]u8{}
+
+	assert true
+}