Revert "[clang-fuzzer] Allow building without coverage instrumentation."

This reverts r315336 due to build breakage with gcc.
http://lab.llvm.org:8011/builders/ubuntu-gcc7.1-werror/builds/2173

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@315355 91177308-0d34-0410-b5e6-96231b3b80d8

tools/clang-fuzzer/CMakeLists.txt

-set(LLVM_LINK_COMPONENTS ${LLVM_TARGETS_TO_BUILD} FuzzMutate)
-set(CXX_FLAGS_NOFUZZ ${CMAKE_CXX_FLAGS})
-set(DUMMY_MAIN DummyClangFuzzer.cpp)
-if(LLVM_USE_SANITIZE_COVERAGE)
+if( LLVM_USE_SANITIZE_COVERAGE )
+  set(LLVM_LINK_COMPONENTS ${LLVM_TARGETS_TO_BUILD})
+  set(CXX_FLAGS_NOFUZZ "${CMAKE_CXX_FLAGS} -fsanitize=fuzzer-no-link")
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=fuzzer")
-  set(CXX_FLAGS_NOFUZZ "${CXX_FLAGS_NOFUZZ} -fsanitize=fuzzer-no-link")
-  unset(DUMMY_MAIN)
-endif()
-
-# Hack to bypass LLVM's cmake sources check and allow multiple libraries and
-# executables from this directory.
-set(LLVM_OPTIONAL_SOURCES
-  ClangFuzzer.cpp
-  DummyClangFuzzer.cpp
-  ExampleClangProtoFuzzer.cpp
-  )
-
-if(CLANG_ENABLE_PROTO_FUZZER)
-  # Create protobuf .h and .cc files, and put them in a library for use by
-  # clang-proto-fuzzer components.
-  find_package(Protobuf REQUIRED)
-  add_definitions(-DGOOGLE_PROTOBUF_NO_RTTI)
-  include_directories(${PROTOBUF_INCLUDE_DIRS})
-  include_directories(${CMAKE_CURRENT_BINARY_DIR})
-  protobuf_generate_cpp(PROTO_SRCS PROTO_HDRS cxx_proto.proto)
-  set(LLVM_OPTIONAL_SOURCES ${LLVM_OPTIONAL_SOURCES} ${PROTO_SRCS})
-  add_clang_library(clangCXXProto
-    ${PROTO_SRCS}
-    ${PROTO_HDRS}
-
-    LINK_LIBS
-    ${PROTOBUF_LIBRARIES}
-    )
 
-  # Build and include libprotobuf-mutator
-  include(ProtobufMutator)
-  include_directories(${ProtobufMutator_INCLUDE_DIRS})
-
-  # Build the protobuf->C++ translation library and driver.
-  add_clang_subdirectory(proto-to-cxx)
-
-  # Build the protobuf fuzzer
-  add_clang_executable(clang-proto-fuzzer
-    ${DUMMY_MAIN}
-    ExampleClangProtoFuzzer.cpp
+  if(CLANG_ENABLE_PROTO_FUZZER)
+    # Create protobuf .h and .cc files, and put them in a library for use by
+    # clang-proto-fuzzer components.
+    find_package(Protobuf REQUIRED)
+    add_definitions(-DGOOGLE_PROTOBUF_NO_RTTI)
+    include_directories(${PROTOBUF_INCLUDE_DIRS})
+    include_directories(${CMAKE_CURRENT_BINARY_DIR})
+    protobuf_generate_cpp(PROTO_SRCS PROTO_HDRS cxx_proto.proto)
+    # Hack to bypass LLVM's cmake sources check and allow multiple libraries and
+    # executables from this directory.
+    set(LLVM_OPTIONAL_SOURCES
+      ClangFuzzer.cpp
+      ExampleClangProtoFuzzer.cpp
+      ${PROTO_SRCS}
+      )
+    add_clang_library(clangCXXProto
+      ${PROTO_SRCS}
+      ${PROTO_HDRS}
+
+      LINK_LIBS
+      ${PROTOBUF_LIBRARIES}
+      )
+
+    # Build and include libprotobuf-mutator
+    include(ProtobufMutator)
+    include_directories(${ProtobufMutator_INCLUDE_DIRS})
+
+    # Build the protobuf->C++ translation library and driver.
+    add_clang_subdirectory(proto-to-cxx)
+
+    # Build the protobuf fuzzer
+    add_clang_executable(clang-proto-fuzzer ExampleClangProtoFuzzer.cpp)
+    target_link_libraries(clang-proto-fuzzer
+      ${ProtobufMutator_LIBRARIES}
+      clangCXXProto
+      clangHandleCXX
+      clangProtoToCXX
+      )
+  else()
+    # Hack to bypass LLVM's cmake sources check and allow multiple libraries and
+    # executables from this directory.
+    set(LLVM_OPTIONAL_SOURCES ClangFuzzer.cpp ExampleClangProtoFuzzer.cpp)
+  endif()
+
+  add_clang_subdirectory(handle-cxx)
+
+  add_clang_executable(clang-fuzzer
+    EXCLUDE_FROM_ALL
+    ClangFuzzer.cpp
     )
 
-  target_link_libraries(clang-proto-fuzzer
-    ${ProtobufMutator_LIBRARIES}
-    clangCXXProto
+  target_link_libraries(clang-fuzzer
     clangHandleCXX
-    clangProtoToCXX
     )
 endif()
-
-add_clang_subdirectory(handle-cxx)
-
-add_clang_executable(clang-fuzzer
-  EXCLUDE_FROM_ALL
-  ${DUMMY_MAIN}
-  ClangFuzzer.cpp
-  )
-
-target_link_libraries(clang-fuzzer
-  clangHandleCXX
-  )

tools/clang-fuzzer/ClangFuzzer.cpp

@@ -17,8 +17,6 @@
 
 using namespace clang_fuzzer;
 
-extern "C" int LLVMFuzzerInitialize(int *argc, char ***argv) { return 0; }
-
 extern "C" int LLVMFuzzerTestOneInput(uint8_t *data, size_t size) {
   std::string s((const char *)data, size);
   HandleCXX(s, {"-O2"});

tools/clang-fuzzer/DummyClangFuzzer.cpp

-//===-- DummyClangFuzzer.cpp - Entry point to sanity check fuzzers --------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// Provides a main() to build without linking libFuzzer.
-//
-//===----------------------------------------------------------------------===//
-#include "llvm/FuzzMutate/FuzzerCLI.h"
-
-extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size);
-extern "C" int LLVMFuzzerInitialize(int *argc, char ***argv);
-
-int main(int argc, char *argv[]) {
-  return llvm::runFuzzerOnInputs(argc, argv, LLVMFuzzerTestOneInput,
-                                 LLVMFuzzerInitialize);
-}