Make lsan complain loudly when running under ptrace

Summary:
LeakSanitizer does not work with ptrace but currently it
will print warnings (only under verbosity=1) and then proceed
to print tons of false reports.
This patch makes lsan fail hard under ptrace with a verbose message.

https://github.com/google/sanitizers/issues/728

Reviewers: eugenis, vitalybuka, aizatsky

Subscribers: kubabrecka, llvm-commits

Differential Revision: https://reviews.llvm.org/D25538

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@284171 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 3 insertions, 1 deletions

diff --git a/lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc b/lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc
index 1ce232b44..eb4c403d3 100644
--- a/lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc
+++ b/lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc
@@ -190,6 +190,7 @@ void ThreadSuspender::KillAllThreads() {
 bool ThreadSuspender::SuspendAllThreads() {
   ThreadLister thread_lister(pid_);
   bool added_threads;
+  bool first_iteration = true;
   do {
     // Run through the directory entries once.
     added_threads = false;
@@ -199,12 +200,13 @@ bool ThreadSuspender::SuspendAllThreads() {
         added_threads = true;
       tid = thread_lister.GetNextTID();
     }
-    if (thread_lister.error()) {
+    if (thread_lister.error() || (first_iteration && !added_threads)) {
       // Detach threads and fail.
       ResumeAllThreads();
       return false;
     }
     thread_lister.Reset();
+    first_iteration = false;
   } while (added_threads);
   return true;
 }