From fe5609d043be8322607abefc56babae0690a39e6 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Tue, 12 Nov 2024 08:51:01 -0300
Subject: [PATCH] cgen: fix generation of a missing return in `return if cond {
 x } else { return missing }` (fix #22838) (#22839)

---
 vlib/v/gen/c/cgen.v                           |  2 ++
 .../gen/c/testdata/if_else_return.c.must_have | 10 +++++++++
 vlib/v/gen/c/testdata/if_else_return.out      |  1 +
 vlib/v/gen/c/testdata/if_else_return.vv       | 21 +++++++++++++++++++
 4 files changed, 34 insertions(+)
 create mode 100644 vlib/v/gen/c/testdata/if_else_return.c.must_have
 create mode 100644 vlib/v/gen/c/testdata/if_else_return.out
 create mode 100644 vlib/v/gen/c/testdata/if_else_return.vv

diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index 59a50eb67..03b587ae7 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -1958,6 +1958,8 @@ fn (mut g Gen) stmts_with_tmp_var(stmts []ast.Stmt, tmp_var string) bool {
 							}
 						}
 					}
+				} else if stmt is ast.Return {
+					g.stmt(stmt)
 				}
 			} else {
 				g.set_current_pos_as_last_stmt_pos()
diff --git a/vlib/v/gen/c/testdata/if_else_return.c.must_have b/vlib/v/gen/c/testdata/if_else_return.c.must_have
new file mode 100644
index 000000000..03926cc73
--- /dev/null
+++ b/vlib/v/gen/c/testdata/if_else_return.c.must_have
@@ -0,0 +1,10 @@
+VV_LOCAL_SYMBOL _result_string main__empty(string s) {
+_result_string _t2; /* if prepend */
+if ((s).len != 0) {
+_result_ok(&(string[]) { s }, (_result*)(&_t2), sizeof(string));
+} else {
+return (_result_string){ .is_error=true, .err=_v_error(_SLIT("empty")), .data={EMPTY_STRUCT_INITIALIZATION} };
+}
+_result_string _t1 =  _t2;
+return _t1;
+}
\ No newline at end of file
diff --git a/vlib/v/gen/c/testdata/if_else_return.out b/vlib/v/gen/c/testdata/if_else_return.out
new file mode 100644
index 000000000..616cb5328
--- /dev/null
+++ b/vlib/v/gen/c/testdata/if_else_return.out
@@ -0,0 +1 @@
+expected error empty
diff --git a/vlib/v/gen/c/testdata/if_else_return.vv b/vlib/v/gen/c/testdata/if_else_return.vv
new file mode 100644
index 000000000..ae29cdea5
--- /dev/null
+++ b/vlib/v/gen/c/testdata/if_else_return.vv
@@ -0,0 +1,21 @@
+fn empty(s string) !string {
+	return if s != '' {
+		s
+	} else {
+		return error('empty')
+	}
+}
+
+fn main() {
+	str_1 := empty('something') or {
+		assert false, 'something is not empty!'
+		return
+	}
+	assert str_1 == 'something'
+
+	str_2 := empty('') or {
+		println('expected error ${err}')
+		return
+	}
+	assert false, 'invalid accepted ${str_2}'
+}
-- 
2.39.5