From fd9cb1a5c565c224897bd49abc5f8c186ba6aaa0 Mon Sep 17 00:00:00 2001
From: Kostya Serebryany <kcc@google.com>
Date: Wed, 8 Jun 2016 01:46:13 +0000
Subject: [PATCH] [libFuzzer] add a test that is built w/o coverage
 instrumentation but has the coverage rt (it should now fail with a
 descriptive message)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272090 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Fuzzer/FuzzerLoop.cpp                     |  5 +++++
 lib/Fuzzer/test/CMakeLists.txt                |  1 +
 lib/Fuzzer/test/fuzzer.test                   |  3 +++
 lib/Fuzzer/test/no-coverage/CMakeLists.txt    | 16 ++++++++++++++++
 lib/Fuzzer/test/uninstrumented/CMakeLists.txt |  3 ++-
 5 files changed, 27 insertions(+), 1 deletion(-)
 create mode 100644 lib/Fuzzer/test/no-coverage/CMakeLists.txt

diff --git a/lib/Fuzzer/FuzzerLoop.cpp b/lib/Fuzzer/FuzzerLoop.cpp
index 5cfbad4c327..e397645782e 100644
--- a/lib/Fuzzer/FuzzerLoop.cpp
+++ b/lib/Fuzzer/FuzzerLoop.cpp
@@ -391,6 +391,11 @@ void Fuzzer::ShuffleAndMinimize() {
   for (auto &X : Corpus)
     UnitHashesAddedToCorpus.insert(Hash(X));
   PrintStats("INITED");
+  if (Corpus.empty()) {
+    Printf("ERROR: no interesting inputs were found. "
+           "Is the code instrumented for coverage? Exiting.\n");
+    exit(1);
+  }
 }
 
 bool Fuzzer::UpdateMaxCoverage() {
diff --git a/lib/Fuzzer/test/CMakeLists.txt b/lib/Fuzzer/test/CMakeLists.txt
index 85fb62e3345..9421606aec0 100644
--- a/lib/Fuzzer/test/CMakeLists.txt
+++ b/lib/Fuzzer/test/CMakeLists.txt
@@ -149,6 +149,7 @@ else()
 endif()
 
 add_subdirectory(uninstrumented)
+add_subdirectory(no-coverage)
 add_subdirectory(ubsan)
 add_subdirectory(trace-bb)
 add_subdirectory(trace-pc)
diff --git a/lib/Fuzzer/test/fuzzer.test b/lib/Fuzzer/test/fuzzer.test
index 25ca5ff5bd2..11343ae3834 100644
--- a/lib/Fuzzer/test/fuzzer.test
+++ b/lib/Fuzzer/test/fuzzer.test
@@ -32,6 +32,9 @@ RUN: not LLVMFuzzer-CallerCalleeTest                     -cross_over=0 -max_len=
 RUN: not LLVMFuzzer-UninstrumentedTest-Uninstrumented 2>&1 | FileCheck %s --check-prefix=UNINSTRUMENTED
 UNINSTRUMENTED: ERROR: __sanitizer_set_death_callback is not defined. Exiting.
 
+RUN: not LLVMFuzzer-UninstrumentedTest-NoCoverage 2>&1 | FileCheck %s --check-prefix=NO_COVERAGE
+NO_COVERAGE: ERROR: no interesting inputs were found. Is the code instrumented for coverage? Exiting
+
 RUN: not LLVMFuzzer-BufferOverflowOnInput 2>&1 | FileCheck %s --check-prefix=OOB
 OOB: AddressSanitizer: heap-buffer-overflow
 OOB: is located 0 bytes to the right of 3-byte region
diff --git a/lib/Fuzzer/test/no-coverage/CMakeLists.txt b/lib/Fuzzer/test/no-coverage/CMakeLists.txt
new file mode 100644
index 00000000000..1dc7d15926c
--- /dev/null
+++ b/lib/Fuzzer/test/no-coverage/CMakeLists.txt
@@ -0,0 +1,16 @@
+# These tests are not instrumented with coverage,
+# but have coverage rt in the binary.
+
+set(CMAKE_CXX_FLAGS
+  "${LIBFUZZER_FLAGS_BASE} -fno-sanitize-coverage=edge,trace-cmp,indirect-calls,8bit-counters")
+
+set(NoCoverageTests
+  UninstrumentedTest
+  )
+
+foreach(Test ${NoCoverageTests})
+  add_libfuzzer_test(${Test}-NoCoverage SOURCES ../${Test}.cpp)
+endforeach()
+
+# Propagate value into parent directory
+set(TestBinaries ${TestBinaries} PARENT_SCOPE)
diff --git a/lib/Fuzzer/test/uninstrumented/CMakeLists.txt b/lib/Fuzzer/test/uninstrumented/CMakeLists.txt
index 35c96481af3..06e48985e7e 100644
--- a/lib/Fuzzer/test/uninstrumented/CMakeLists.txt
+++ b/lib/Fuzzer/test/uninstrumented/CMakeLists.txt
@@ -1,4 +1,5 @@
-# These tests are not instrumented with coverage.
+# These tests are not instrumented with coverage and don't
+# have coverage rt in the binary.
 
 set(CMAKE_CXX_FLAGS
   "${LIBFUZZER_FLAGS_BASE} -fno-sanitize=all -fno-sanitize-coverage=edge,trace-cmp,indirect-calls,8bit-counters")
-- 
2.11.0