diff --git a/test/fuzz_unpack_pack_fuzzer.cpp b/test/fuzz_unpack_pack_fuzzer.cpp
index 56fb28f9..a7db076c 100644
--- a/test/fuzz_unpack_pack_fuzzer.cpp
+++ b/test/fuzz_unpack_pack_fuzzer.cpp
@@ -2,8 +2,6 @@
 
 #include "../fuzz/unpack_pack_fuzzer.cc"
 
-extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);
-
 TEST(FUZZ_UNPACK_PACK_FUZZER, works)
 {
   EXPECT_EQ(0, LLVMFuzzerTestOneInput(0, 0));