Update LLVM fuzzers to use the libFuzzer bundled with the compiler toolchain

[george.karpenkov]

Summary

The only current downside is that on mac fuzzing only works when ASAN_OPTIONS=detect_container_overflow=0 is specified.
This happens as libFuzzer itself is not compiled with sanitization anymore.
I am working on a fix for that.

[george.karpenkov]

cmake/modules/HandleLLVMOptions.cmake

667

This is important. Otherwise, libFuzzer dies with a message about inconsistent coverage annotation.

tools/llvm-dwarfdump/fuzzer/llvm-dwarfdump-fuzzer.cpp

39

Had to fix this file, otherwise wouldn't compile.

tools/llvm-mc-assemble-fuzzer/llvm-mc-assemble-fuzzer.cpp

12

No trivial path to it anymore, and unclear why it was included.

[kcc]

LGTM
Please don't add samsonov@ to reviews -- he has left the team :(
Please add morehouse@ and vitalybuka@ instead.

cmake/modules/HandleLLVMOptions.cmake

if(LLVM_USE_SANITIZER)
   else()
     message(FATAL_ERROR "LLVM_USE_SANITIZER is not supported on this platform.")
   endif()
   if (LLVM_USE_SANITIZER MATCHES "(Undefined;)?Address(;Undefined)?")
     add_flag_if_supported("-fsanitize-address-use-after-scope"
                           FSANITIZE_USE_AFTER_SCOPE_FLAG)
   endif()
   if (LLVM_USE_SANITIZE_COVERAGE)
-    append("-fsanitize-coverage=trace-pc-guard,indirect-calls,trace-cmp" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
+    append("-fsanitize=fuzzer-no-link" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
   endif()
 endif()
 
 # Turn on -gsplit-dwarf if requested
 if(LLVM_USE_SPLIT_DWARF)
   add_definitions("-gsplit-dwarf")
 endif()
 

tools/llvm-as-fuzzer/CMakeLists.txt

 if( LLVM_USE_SANITIZE_COVERAGE )
+
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=fuzzer")
   set(LLVM_LINK_COMPONENTS
       AsmParser
       BitWriter
       Core
       Support
       )
-  add_llvm_tool(llvm-as-fuzzer 
+  add_llvm_tool(llvm-as-fuzzer
                 llvm-as-fuzzer.cpp)
-  target_link_libraries(llvm-as-fuzzer
-                        LLVMFuzzer
-                        )
 endif()

tools/llvm-dwarfdump/fuzzer/CMakeLists.txt

 set(LLVM_LINK_COMPONENTS
   DebugInfoDWARF
   Object
   Support
   )
 
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=fuzzer")
+
 add_llvm_executable(llvm-dwarfdump-fuzzer
   EXCLUDE_FROM_ALL
   llvm-dwarfdump-fuzzer.cpp
   )
-
-target_link_libraries(llvm-dwarfdump-fuzzer
-  LLVMFuzzer
-  )

tools/llvm-dwarfdump/fuzzer/llvm-dwarfdump-fuzzer.cpp

extern "C" void LLVMFuzzerTestOneInput(uint8_t *data, size_t size) {
   Expected<std::unique_ptr<ObjectFile>> ObjOrErr =
       ObjectFile::createObjectFile(Buff->getMemBufferRef());
   if (auto E = ObjOrErr.takeError()) {
     consumeError(std::move(E));
     return;
   }
   ObjectFile &Obj = *ObjOrErr.get();
   std::unique_ptr<DIContext> DICtx = DWARFContext::create(Obj);
-  DICtx->dump(nulls(), DIDT_All);
+
+
+  DIDumpOptions opts;
+  opts.DumpType = DIDT_All;
+  DICtx->dump(nulls(), opts);
 }

tools/llvm-mc-assemble-fuzzer/CMakeLists.txt

 if( LLVM_USE_SANITIZE_COVERAGE )
-  include_directories(BEFORE
-    ${CMAKE_CURRENT_SOURCE_DIR}/../../lib/Fuzzer)
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=fuzzer")
 
   set(LLVM_LINK_COMPONENTS
       AllTargetsAsmPrinters
       AllTargetsAsmParsers
       AllTargetsDescs
       AllTargetsInfos
       MC
       MCParser
       Support
       )
-  add_llvm_tool(llvm-mc-assemble-fuzzer 
+
+  add_llvm_tool(llvm-mc-assemble-fuzzer
                 llvm-mc-assemble-fuzzer.cpp)
-  target_link_libraries(llvm-mc-assemble-fuzzer
-                        LLVMFuzzer
-                        )
 endif()

tools/llvm-mc-assemble-fuzzer/llvm-mc-assemble-fuzzer.cpp

 //===--- llvm-mc-fuzzer.cpp - Fuzzer for the MC layer ---------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 //===----------------------------------------------------------------------===//
 
-#include "FuzzerInterface.h"
 #include "llvm-c/Target.h"
 #include "llvm/MC/SubtargetFeature.h"
 #include "llvm/MC/MCAsmBackend.h"
 #include "llvm/MC/MCAsmInfo.h"
 #include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCInstPrinter.h"
 #include "llvm/MC/MCInstrInfo.h"
 #include "llvm/MC/MCObjectFileInfo.h"

tools/llvm-mc-disassemble-fuzzer/CMakeLists.txt

 if( LLVM_USE_SANITIZE_COVERAGE )
-  include_directories(BEFORE
-    ${CMAKE_CURRENT_SOURCE_DIR}/../../lib/Fuzzer)
 
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=fuzzer")
   set(LLVM_LINK_COMPONENTS
       AllTargetsAsmPrinters
       AllTargetsDescs
       AllTargetsDisassemblers
       AllTargetsInfos
       MC
       MCDisassembler
       MCParser
       Support
       )
-  add_llvm_tool(llvm-mc-disassemble-fuzzer 
+  add_llvm_tool(llvm-mc-disassemble-fuzzer
                 llvm-mc-disassemble-fuzzer.cpp)
-
-  target_link_libraries(llvm-mc-disassemble-fuzzer
-                        LLVMFuzzer
-                        )
 endif()

tools/llvm-mc-disassemble-fuzzer/llvm-mc-disassemble-fuzzer.cpp

 //===--- llvm-mc-fuzzer.cpp - Fuzzer for the MC layer ---------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 //===----------------------------------------------------------------------===//
 
-#include "FuzzerInterface.h"
 #include "llvm-c/Disassembler.h"
 #include "llvm-c/Target.h"
 #include "llvm/MC/SubtargetFeature.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/raw_ostream.h"
 
 using namespace llvm;