cgen: fix translated file fixed-array assignment (#25080)

Author: kbkpbot

vlib/v/gen/c/assign.v

@@ -508,12 +508,14 @@ fn (mut g Gen) assign_stmt(node_ ast.AssignStmt) {
 		unwrapped_val_type := g.unwrap_generic(val_type)
 		right_sym := g.table.sym(unwrapped_val_type)
 		unaliased_right_sym := g.table.final_sym(unwrapped_val_type)
-		is_fixed_array_var := !g.pref.translated && unaliased_right_sym.kind == .array_fixed
-			&& val !is ast.ArrayInit
+		unaliased_left_sym := g.table.final_sym(g.unwrap_generic(var_type))
+		is_fixed_array_var := unaliased_right_sym.kind == .array_fixed && val !is ast.ArrayInit
 			&& (val in [ast.Ident, ast.IndexExpr, ast.CallExpr, ast.SelectorExpr, ast.DumpExpr, ast.InfixExpr]
 			|| (val is ast.CastExpr && val.expr !is ast.ArrayInit)
 			|| (val is ast.PrefixExpr && val.op == .arrow)
 			|| (val is ast.UnsafeExpr && val.expr in [ast.SelectorExpr, ast.Ident, ast.CallExpr]))
+			&& !((g.pref.translated || g.file.is_translated)
+			&& unaliased_left_sym.kind != .array_fixed)
 		g.is_assign_lhs = true
 		g.assign_op = node.op
 
@@ -553,10 +555,18 @@ fn (mut g Gen) assign_stmt(node_ ast.AssignStmt) {
 				}
 				g.writeln(';}')
 			}
-		} else if node.op == .assign && !g.pref.translated && (is_fixed_array_init
+		} else if node.op == .assign && (is_fixed_array_init
 			|| (unaliased_right_sym.kind == .array_fixed && val in [ast.Ident, ast.CastExpr])) {
 			// Fixed arrays
-			if is_fixed_array_init && var_type.has_flag(.option) {
+			if unaliased_left_sym.kind != .array_fixed && unaliased_right_sym.kind == .array_fixed
+				&& (g.pref.translated || g.file.is_translated) {
+				// translated:
+				// arr = [5]u8{}
+				// ptr = arr   => ptr = &arr[0]
+				g.expr(left)
+				g.write(' = ')
+				g.expr(val)
+			} else if is_fixed_array_init && var_type.has_flag(.option) {
 				g.expr(left)
 				g.write(' = ')
 				g.expr_with_opt(val, val_type, var_type)

vlib/v/tests/translated_test.v

@@ -12,3 +12,36 @@ const ssf = [1, 2, 3]!
 fn test_const_name_without_main_prefix() {
 	assert ssf[0] == 1
 }
+
+struct ASMOperand {
+	constraint [2]i8
+}
+
+fn test_pointer_assign_without_memcpy() {
+	op := ASMOperand{
+		constraint: [i8(5), 4]!
+	}
+	str := &i8(0)
+	str = op.constraint
+	assert !isnil(str)
+
+	ops := [3]ASMOperand{}
+	pop := &ASMOperand(0)
+	pop = ops
+	assert pop[1].constraint[0] == 0
+}
+
+struct StubIndex {
+pub mut:
+	data [5][5]map[string]string
+}
+
+fn test_pointer_assign_with_memcpy() {
+	mut s := StubIndex{}
+	s.data[1] = [5]map[string]string{}
+
+	mut data := s.data[1]
+	data[0]['abc'] = '123'
+	k := data[0]['abc']
+	assert k == '123'
+}