analyzer: check borrow returns of forward-called functions at the unit's end; borrows clause for prototypes, definitions, externs and function types, checked against the body

1 files changed, 11 insertions, 0 deletions

diff --git a/tests/programs/borrows_clause.zc b/tests/programs/borrows_clause.zc
new file mode 100644
index 0000000..6f43581
--- /dev/null
+++ b/tests/programs/borrows_clause.zc
@@ -0,0 +1,11 @@
+namespace;
+include rt;
+// a borrows clause on a prototype and its definition: freeing the other argument keeps the result.
+char* first(char* a, char* b) borrows a;
+fn main() {
+	char* t = rt.new(4); t[0] = 'x'; t[1] = 0;
+	char* u = rt.new(4); u[0] = 'y'; u[1] = 0;
+	let r = first(t, u); rt.free(u); rt.put_c(r[0]); rt.free(t);
+	return 0;
+}
+char* first(char* a, char* b) borrows a { return a; }