1 files changed, 38 insertions, 0 deletions
diff --git a/compiler-rt/test/asan/TestCases/pass-struct-byval-uar.cpp b/compiler-rt/test/asan/TestCases/pass-struct-byval-uar.cpp
new file mode 100644
index 00000000000..aa6fa579e18
--- /dev/null
+++ b/compiler-rt/test/asan/TestCases/pass-struct-byval-uar.cpp
@@ -0,0 +1,38 @@
+// Test that use-after-return works with arguments passed by value.
+// RUN: %clangxx_asan -O0 %s -o %t
+// RUN: %env_asan_opts=detect_stack_use_after_return=0 %run %t 2>&1 | \
+// RUN:     FileCheck --check-prefix=CHECK-NO-UAR %s
+// RUN: not %env_asan_opts=detect_stack_use_after_return=1 %run %t 2>&1 | \
+// RUN:     FileCheck --check-prefix=CHECK-UAR %s
+//
+// On several architectures, the IR does not use byval arguments for foo() and
+// instead creates a copy in main() and gives foo() a pointer to the copy.  In
+// that case, ASAN has nothing to poison on return from foo() and will not
+// detect the UAR.
+// REQUIRES: x86_64-target-arch, linux, !android
+
+#include <cstdio>
+
+struct A {
+  int a[8];
+};
+
+A *foo(A a) {
+  return &a;
+}
+
+int main() {
+  A *a = foo(A());
+  a->a[0] = 7;
+  std::fprintf(stderr, "\n");  // Ensures some output is generated for FileCheck
+                               // to verify in the case where UAR is not
+                               // detected.
+}
+
+// CHECK-NO-UAR-NOT: ERROR: AddressSanitizer: stack-use-after-return
+// CHECK-NO-UAR-NOT: WRITE of size 4 at
+// CHECK-NO-UAR-NOT: Memory access at offset {{[0-9]+}} is inside this variable
+//
+// CHECK-UAR: ERROR: AddressSanitizer: stack-use-after-return
+// CHECK-UAR: WRITE of size 4 at
+// CHECK-UAR: Memory access at offset {{[0-9]+}} is inside this variable