[libFuzzer] add an assert to protect against LLVMFuzzerInitialize changing argv[0]

llvm-svn: 292652

1 files changed, 15 insertions, 0 deletions

diff --git a/llvm/lib/Fuzzer/test/BogusInitializeTest.cpp b/llvm/lib/Fuzzer/test/BogusInitializeTest.cpp
new file mode 100644
index 00000000000..c7e81a5478b
--- /dev/null
+++ b/llvm/lib/Fuzzer/test/BogusInitializeTest.cpp
@@ -0,0 +1,15 @@
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+
+// Make sure LLVMFuzzerInitialize does not change argv[0].
+#include <stddef.h>
+#include <stdint.h>
+
+extern "C" int LLVMFuzzerInitialize(int *argc, char ***argv) {
+  ***argv = 'X';
+  return 0;
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+  return 0;
+}