third_party/re2/patches/re2-msan.patch

diff --git a/third_party/re2/util/sparse_array.h b/third_party/re2/util/sparse_array.h
index 3e33f89..4ee5c94 100644
--- a/third_party/re2/util/sparse_array.h
+++ b/third_party/re2/util/sparse_array.h
@@ -231,7 +231,8 @@ class SparseArray {
 
 template<typename Value>
 SparseArray<Value>::SparseArray()
-    : size_(0), max_size_(0), sparse_to_dense_(NULL), dense_(), valgrind_(RunningOnValgrind()) {}
+    : size_(0), max_size_(0), sparse_to_dense_(NULL), dense_(),
+      valgrind_(RunningOnValgrindOrMemorySanitizer()) {}
 
 // IndexValue pairs: exposed in SparseArray::iterator.
 template<typename Value>
@@ -418,7 +419,7 @@ void SparseArray<Value>::create_index(int i) {
 template<typename Value> SparseArray<Value>::SparseArray(int max_size) {
   max_size_ = max_size;
   sparse_to_dense_ = new int[max_size];
-  valgrind_ = RunningOnValgrind();
+  valgrind_ = RunningOnValgrindOrMemorySanitizer();
   dense_.resize(max_size);
   // Don't need to zero the new memory, but appease Valgrind.
   if (valgrind_) {
diff --git a/third_party/re2/util/sparse_set.h b/third_party/re2/util/sparse_set.h
index 165dd09..4a324d7 100644
--- a/third_party/re2/util/sparse_set.h
+++ b/third_party/re2/util/sparse_set.h
@@ -54,13 +54,14 @@ namespace re2 {
 class SparseSet {
  public:
   SparseSet()
-    : size_(0), max_size_(0), sparse_to_dense_(NULL), dense_(NULL), valgrind_(RunningOnValgrind()) {}
+    : size_(0), max_size_(0), sparse_to_dense_(NULL), dense_(NULL),
+      valgrind_(RunningOnValgrindOrMemorySanitizer()) {}
 
   SparseSet(int max_size) {
     max_size_ = max_size;
     sparse_to_dense_ = new int[max_size];
     dense_ = new int[max_size];
-    valgrind_ = RunningOnValgrind();
+    valgrind_ = RunningOnValgrindOrMemorySanitizer();
     // Don't need to zero the memory, but do so anyway
     // to appease Valgrind.
     if (valgrind_) {
diff --git a/third_party/re2/util/util.h b/third_party/re2/util/util.h
index de1ef5b..49159c2 100644
--- a/third_party/re2/util/util.h
+++ b/third_party/re2/util/util.h
@@ -129,6 +129,14 @@ static inline uint64 Hash64StringWithSeed(const char* s, int len, uint32 seed) {
   return ((uint64)x << 32) | y;
 }
 
+inline bool RunningOnValgrindOrMemorySanitizer() {
+#if defined(MEMORY_SANITIZER)
+  return true;
+#else
+  return RunningOnValgrind();
+#endif
+}
+
 }  // namespace re2
 
 #include "util/arena.h"