cef/patch/patches/third_party_sentencepiece_3...

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diff --git third_party/sentencepiece/src/src/util.cc third_party/sentencepiece/src/src/util.cc
index c5e5289807a0c..e10880abc17eb 100644
--- third_party/sentencepiece/src/src/util.cc
+++ third_party/sentencepiece/src/src/util.cc
@@ -16,6 +16,7 @@
#include <atomic>
#include <iostream>
+#include <memory>
namespace sentencepiece {
@@ -197,8 +198,18 @@ std::mt19937 *GetRandomGenerator() {
}
#else
std::mt19937 *GetRandomGenerator() {
- thread_local static std::mt19937 mt(GetRandomGeneratorSeed());
- return &mt;
+ // Thread-locals occupy stack space in every thread ever created by the
+ // program, even if that thread never uses the thread-local variable.
+ //
+ // https://maskray.me/blog/2021-02-14-all-about-thread-local-storage
+ //
+ // sizeof(std::mt19937) is several kilobytes, so it is safer to put that on
+ // the heap, leaving only a pointer to it in thread-local storage. This must
+ // be a unique_ptr, not a raw pointer, so that the generator is not leaked on
+ // thread exit.
+ thread_local static auto mt =
+ std::make_unique<std::mt19937>(GetRandomGeneratorSeed());
+ return mt.get();
}
#endif
} // namespace random