diff --git a/cmd/tools/vtest-self.v b/cmd/tools/vtest-self.v
index 0ca889e292..ae0f601f8a 100644
--- a/cmd/tools/vtest-self.v
+++ b/cmd/tools/vtest-self.v
@@ -105,6 +105,7 @@ const (
 		'vlib/v/tests/interface_edge_cases/assign_to_interface_field_test.v',
 		'vlib/v/tests/interface_fields_test.v',
 		'vlib/v/tests/interface_variadic_test.v',
+		'vlib/v/tests/option_2_test.v',
 		'vlib/v/tests/orm_sub_struct_test.v',
 		'vlib/v/tests/ref_struct_test.v',
 		'vlib/v/tests/semaphore_test.v',
diff --git a/vlib/v/ast/ast.v b/vlib/v/ast/ast.v
index de5aed918d..19cb2fec35 100644
--- a/vlib/v/ast/ast.v
+++ b/vlib/v/ast/ast.v
@@ -1280,7 +1280,9 @@ pub fn (expr Expr) is_lvalue() bool {
 pub fn (expr Expr) is_expr() bool {
 	match expr {
 		IfExpr { return expr.is_expr }
+		LockExpr { return expr.is_expr }
 		MatchExpr { return expr.is_expr }
+		SelectExpr { return expr.is_expr }
 		else {}
 	}
 	return true
diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index 3ea8c0cc61..c5728bea8e 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -3670,7 +3670,11 @@ pub fn (mut c Checker) expr(node ast.Expr) table.Type {
 			return c.cast_expr(mut node)
 		}
 		ast.CallExpr {
-			return c.call_expr(mut node)
+			mut ret_type := c.call_expr(mut node)
+			if ret_type.has_flag(.optional) && node.or_block.kind != .absent {
+				ret_type = ret_type.clear_flag(.optional)
+			}
+			return ret_type
 		}
 		ast.GoExpr {
 			mut ret_type := c.call_expr(mut node.go_stmt.call_expr)
diff --git a/vlib/v/checker/tests/return_optional_err.out b/vlib/v/checker/tests/return_optional_err.out
deleted file mode 100644
index e7066fcfea..0000000000
--- a/vlib/v/checker/tests/return_optional_err.out
+++ /dev/null
@@ -1,7 +0,0 @@
-vlib/v/checker/tests/return_optional_err.vv:4:13: error: cannot use `?string` as type `string` in return argument
-    2 |
-    3 | fn my_func() string {
-    4 |   return os.read_file('/some/file/that/exists.txt') or { panic(err.msg) }
-      |             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-    5 | }
-    6 |
diff --git a/vlib/v/checker/tests/return_optional_err.vv b/vlib/v/checker/tests/return_optional_err.vv
deleted file mode 100644
index 03be0efe75..0000000000
--- a/vlib/v/checker/tests/return_optional_err.vv
+++ /dev/null
@@ -1,10 +0,0 @@
-import os
-
-fn my_func() string {
-  return os.read_file('/some/file/that/exists.txt') or { panic(err.msg) }
-}
-
-fn main() {
-	aa := my_func()
-	println(aa)
-}
diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index 09c13c2939..f3a2a967f6 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -65,7 +65,8 @@ mut:
 	tmp_count2          int  // a separate tmp var counter for autofree fn calls
 	is_c_call           bool // e.g. `C.printf("v")`
 	is_assign_lhs       bool // inside left part of assign expr (for array_set(), etc)
-	is_assign_rhs       bool // inside right part of assign after `=` (val expr)
+	discard_or_result   bool // do not safe last ExprStmt of `or` block in tmp variable to defer ongoing expr usage
+	is_void_expr_stmt   bool // ExprStmt whos result is discarded
 	is_array_set        bool
 	is_amp              bool // for `&Foo{}` to merge PrefixExpr `&` and StructInit `Foo{}`; also for `&byte(0)` etc
 	is_sql              bool // Inside `sql db{}` statement, generating sql instead of C (e.g. `and` instead of `&&` etc)
@@ -1068,7 +1069,10 @@ fn (mut g Gen) stmt(node ast.Stmt) {
 			// if af {
 			// g.autofree_call_pregen(node.expr as ast.CallExpr)
 			// }
+			old_is_void_expr_stmt := g.is_void_expr_stmt
+			g.is_void_expr_stmt = !node.is_expr
 			g.expr(node.expr)
+			g.is_void_expr_stmt = old_is_void_expr_stmt
 			// if af {
 			// g.autofree_call_postgen()
 			// }
@@ -1758,9 +1762,7 @@ fn (mut g Gen) gen_assign_stmt(assign_stmt ast.AssignStmt) {
 			mr_var_name := 'mr_$assign_stmt.pos.pos'
 			mr_styp := g.typ(return_type)
 			g.write('$mr_styp $mr_var_name = ')
-			g.is_assign_rhs = true
 			g.expr(assign_stmt.right[0])
-			g.is_assign_rhs = false
 			g.writeln(';')
 			for i, lx in assign_stmt.left {
 				if lx is ast.Ident {
@@ -1947,7 +1949,10 @@ fn (mut g Gen) gen_assign_stmt(assign_stmt ast.AssignStmt) {
 		}
 		if blank_assign {
 			if is_call {
+				old_is_void_expr_stmt := g.is_void_expr_stmt
+				g.is_void_expr_stmt = true
 				g.expr(val)
+				g.is_void_expr_stmt = old_is_void_expr_stmt
 			} else {
 				g.write('{$styp _ = ')
 				g.expr(val)
@@ -2000,7 +2005,6 @@ fn (mut g Gen) gen_assign_stmt(assign_stmt ast.AssignStmt) {
 					g.write(' = /*f*/string_add(')
 				}
 				g.is_assign_lhs = false
-				g.is_assign_rhs = true
 				str_add = true
 			}
 			// Assignment Operator Overloading
@@ -2053,7 +2057,6 @@ fn (mut g Gen) gen_assign_stmt(assign_stmt ast.AssignStmt) {
 				g.expr(left)
 			}
 			g.is_assign_lhs = false
-			g.is_assign_rhs = true
 			if is_fixed_array_copy {
 				if is_decl {
 					g.writeln(';')
@@ -2080,7 +2083,6 @@ fn (mut g Gen) gen_assign_stmt(assign_stmt ast.AssignStmt) {
 					g.write('*($styp*)')
 					g.write(tmp_opt + '.data/*FFz*/')
 					g.right_is_opt = false
-					g.is_assign_rhs = false
 					if g.inside_ternary == 0 && !assign_stmt.is_simple {
 						g.writeln(';')
 					}
@@ -2144,7 +2146,6 @@ fn (mut g Gen) gen_assign_stmt(assign_stmt ast.AssignStmt) {
 			g.is_shared = false
 		}
 		g.right_is_opt = false
-		g.is_assign_rhs = false
 		if g.inside_ternary == 0 && (assign_stmt.left.len > 1 || !assign_stmt.is_simple) {
 			g.writeln(';')
 		}
@@ -2468,6 +2469,14 @@ fn (mut g Gen) map_fn_ptrs(key_typ table.TypeSymbol) (string, string, string, st
 
 fn (mut g Gen) expr(node ast.Expr) {
 	// println('cgen expr() line_nr=$node.pos.line_nr')
+	old_discard_or_result := g.discard_or_result
+	old_is_void_expr_stmt := g.is_void_expr_stmt
+	if g.is_void_expr_stmt {
+		g.discard_or_result = true
+		g.is_void_expr_stmt = false
+	} else {
+		g.discard_or_result = false
+	}
 	// NB: please keep the type names in the match here in alphabetical order:
 	match mut node {
 		ast.AnonFn {
@@ -2733,7 +2742,7 @@ fn (mut g Gen) expr(node ast.Expr) {
 				right_sym := g.table.get_type_symbol(node.right_type)
 				mut right_inf := right_sym.info as table.Chan
 				elem_type := right_inf.elem_type
-				is_gen_or_and_assign_rhs := gen_or && g.is_assign_rhs
+				is_gen_or_and_assign_rhs := gen_or && !g.discard_or_result
 				cur_line := if is_gen_or_and_assign_rhs {
 					line := g.go_before_stmt(0)
 					g.out.write_string(c.tabs[g.indent])
@@ -2831,6 +2840,8 @@ fn (mut g Gen) expr(node ast.Expr) {
 			g.expr(node.expr)
 		}
 	}
+	g.discard_or_result = old_discard_or_result
+	g.is_void_expr_stmt = old_is_void_expr_stmt
 }
 
 // T.name, typeof(expr).name
@@ -4320,7 +4331,7 @@ fn (mut g Gen) index_expr(node ast.IndexExpr) {
 					}
 					needs_clone := info.elem_type == table.string_type_idx && g.is_autofree
 						&& !g.is_assign_lhs
-					is_gen_or_and_assign_rhs := gen_or && g.is_assign_rhs
+					is_gen_or_and_assign_rhs := gen_or && !g.discard_or_result
 					cur_line := if is_gen_or_and_assign_rhs {
 						line := g.go_before_stmt(0)
 						g.out.write_string(c.tabs[g.indent])
@@ -4493,7 +4504,7 @@ fn (mut g Gen) index_expr(node ast.IndexExpr) {
 					g.write('}, &($elem_type_str[]){ $zero }))')
 				} else {
 					zero := g.type_default(info.value_type)
-					is_gen_or_and_assign_rhs := gen_or && g.is_assign_rhs
+					is_gen_or_and_assign_rhs := gen_or && !g.discard_or_result
 					cur_line := if is_gen_or_and_assign_rhs {
 						line := g.go_before_stmt(0)
 						g.out.write_string(c.tabs[g.indent])
@@ -4724,11 +4735,15 @@ fn (mut g Gen) return_statement(node ast.Return) {
 	} else if node.exprs.len >= 1 {
 		// normal return
 		return_sym := g.table.get_type_symbol(node.types[0])
-		// `return opt_ok(expr)` for functions that expect an optional
-		mut expr_type_is_opt := node.types[0].has_flag(.optional)
 		expr0 := node.exprs[0]
-		if expr0 is ast.CallExpr {
-			expr_type_is_opt = expr0.return_type.has_flag(.optional)
+		// `return opt_ok(expr)` for functions that expect an optional
+		expr_type_is_opt := match expr0 {
+			ast.CallExpr {
+				expr0.return_type.has_flag(.optional) && expr0.or_block.kind == .absent
+			}
+			else {
+				node.types[0].has_flag(.optional)
+			}
 		}
 		if fn_return_is_optional && !expr_type_is_opt && return_sym.name !in ['Option', 'Option2'] {
 			styp := g.base_type(g.fn_decl.return_type)
diff --git a/vlib/v/gen/c/fn.v b/vlib/v/gen/c/fn.v
index 5dccd53909..4a622f2dc6 100644
--- a/vlib/v/gen/c/fn.v
+++ b/vlib/v/gen/c/fn.v
@@ -410,7 +410,7 @@ fn (mut g Gen) call_expr(node ast.CallExpr) {
 		g.inside_call = false
 	}
 	gen_or := node.or_block.kind != .absent // && !g.is_autofree
-	is_gen_or_and_assign_rhs := gen_or && g.is_assign_rhs
+	is_gen_or_and_assign_rhs := gen_or && !g.discard_or_result
 	cur_line := if is_gen_or_and_assign_rhs { // && !g.is_autofree {
 		// `x := foo() or { ...}`
 		// cut everything that has been generated to prepend optional variable creation
@@ -421,14 +421,8 @@ fn (mut g Gen) call_expr(node ast.CallExpr) {
 	} else {
 		''
 	}
-	// if gen_or && g.pref.autofree && g.inside_return {
-	if gen_or && g.inside_return {
-		// TODO optional return af hack (tmp_count gets increased in .return_statement())
-		g.tmp_count--
-	}
 	tmp_opt := if gen_or { g.new_tmp_var() } else { '' }
-	if gen_or && !g.inside_return {
-		// if is_gen_or_and_assign_rhs {
+	if gen_or {
 		styp := g.typ(node.return_type.set_flag(.optional))
 		g.write('$styp $tmp_opt = ')
 	}
@@ -455,10 +449,10 @@ fn (mut g Gen) call_expr(node ast.CallExpr) {
 			} else if g.table.get_type_symbol(node.return_type).kind == .multi_return {
 				g.write('\n $cur_line $tmp_opt /*U*/')
 			} else {
-				g.write('\n $cur_line *($unwrapped_styp*)${tmp_opt}.data')
+				if !g.inside_const {
+					g.write('\n $cur_line *($unwrapped_styp*)${tmp_opt}.data')
+				}
 			}
-			// g.write('\n /*call_expr cur_line:*/ $cur_line /*C*/ $tmp_opt /*end*/')
-			// g.insert_before_stmt('\n /* VVV */ $tmp_opt')
 		}
 	}
 }
diff --git a/vlib/v/tests/option_2_test.v b/vlib/v/tests/option_2_test.v
new file mode 100644
index 0000000000..7404fd265c
--- /dev/null
+++ b/vlib/v/tests/option_2_test.v
@@ -0,0 +1,59 @@
+fn f(n int) ?int {
+	if n < 0 {
+		return error('negative arg')
+	}
+	return n
+}
+
+fn test_lhs_option() {
+	mut a := [0, 1, 2, 3, 4]
+	a[f(-1) or { 2 }] = 7
+	assert a == [0, 1, 7, 3, 4]
+}
+
+fn ret_no_opt(n int) int {
+	return f(n) or { panic(err.msg) }
+}
+
+fn test_opt_return_no_opt() {
+	aa := ret_no_opt(3)
+	assert aa == 3
+}
+
+fn test_range_for_and_array_push() {
+	mut a := []int{}
+	for n in f(-3) or { -1 } .. f(3) or { 12 } {
+		a << f(n) or { -5 }
+	}
+	assert a == [-5, 0, 1, 2]
+}
+
+fn test_channel_push() {
+	ch := chan f64{cap: 2}
+	ch <- 12.25
+	ch.close()
+	mut res := []f64{cap: 3}
+	for _ in 0 .. 3 {
+		res << <-ch or { -6.75 }
+	}
+	assert res == [12.25, -6.75, -6.75]
+}
+
+fn test_thread_wait() {
+	thrs := [
+		go f(3)
+		go f(-7)
+		go f(12)
+	]
+	mut res := []int{cap: 3}
+	for t in thrs {
+		res << t.wait() or { -13 }
+	}
+	assert res == [3, -13, 12]
+}
+
+fn test_nested_opt() {
+	a := f(f(f(-3) or { -7 }) or { 4 }) or { 17 }
+	assert a == 4
+}
+