[libFuzzer] Make -fsanitize=memory,fuzzer work.

This patch allows libFuzzer to fuzz applications instrumented with MSan
without recompiling libFuzzer with MSan instrumentation.

Fixes https://github.com/google/sanitizers/issues/958.

Differential Revision: https://reviews.llvm.org/D48891

llvm-svn: 336619

1 files changed, 9 insertions, 2 deletions

diff --git a/compiler-rt/test/fuzzer/lit.cfg b/compiler-rt/test/fuzzer/lit.cfg
index 44d8f4e0375..cdd1d73d3c0 100644
--- a/compiler-rt/test/fuzzer/lit.cfg
+++ b/compiler-rt/test/fuzzer/lit.cfg
@@ -49,7 +49,7 @@ config.substitutions.append(('%build_dir', config.cmake_binary_dir))
 libfuzzer_src_root = os.path.join(config.compiler_rt_src_root, "lib", "fuzzer")
 config.substitutions.append(('%libfuzzer_src', libfuzzer_src_root))
 
-def generate_compiler_cmd(is_cpp=True, fuzzer_enabled=True):
+def generate_compiler_cmd(is_cpp=True, fuzzer_enabled=True, msan_enabled=False):
   compiler_cmd = config.clang
   extra_cmd = config.target_flags
   if config.clang and config.stdlib == 'libc++':
@@ -63,7 +63,10 @@ def generate_compiler_cmd(is_cpp=True, fuzzer_enabled=True):
     link_cmd = '-lstdc++'
 
   std_cmd = '--driver-mode=g++ -std=c++11' if is_cpp else ''
-  sanitizers = ['address']
+  if msan_enabled:
+    sanitizers = ['memory']
+  else:
+    sanitizers = ['address']
   if fuzzer_enabled:
     sanitizers.append('fuzzer')
   sanitizers_cmd = ('-fsanitize=%s' % ','.join(sanitizers))
@@ -93,6 +96,10 @@ config.substitutions.append(('%no_fuzzer_c_compiler',
       generate_compiler_cmd(is_cpp=False, fuzzer_enabled=False)
       ))
 
+config.substitutions.append(('%msan_compiler',
+      generate_compiler_cmd(is_cpp=True, fuzzer_enabled=True, msan_enabled=True)
+      ))
+
 if config.host_os == 'Darwin':
   if config.target_arch in ["x86_64", "x86_64h"]:
     config.parallelism_group = "darwin-64bit-sanitizer"