If lldb is being built with ASAN instrumentation, have lldb

create its own threads with 8MB additional maximum stack size.
Extra room is needed for the bookkeeping needed for this 
instrumentation.

llvm-svn: 227421

lldb/source/Host/common/ThreadLauncher.cpp

@@ -38,6 +38,16 @@ ThreadLauncher::LaunchThread(llvm::StringRef name, lldb::thread_func_t thread_fu
         error.SetError(::GetLastError(), eErrorTypeWin32);
 #else
 
+
+    // ASAN instrumentation adds a lot of bookkeeping overhead on stack frames.
+#if __has_feature(address_sanitizer)
+    const size_t eight_megabytes = 8 * 1024 * 1024;
+    if (min_stack_byte_size < eight_megabytes)
+    {
+        min_stack_byte_size += eight_megabytes;
+    }
+#endif
+
     pthread_attr_t *thread_attr_ptr = NULL;
     pthread_attr_t thread_attr;
     bool destroy_attr = false;