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-rw-r--r--third_party/abseil-cpp/absl/random/internal/randen_engine.h15
1 files changed, 12 insertions, 3 deletions
diff --git a/third_party/abseil-cpp/absl/random/internal/randen_engine.h b/third_party/abseil-cpp/absl/random/internal/randen_engine.h
index 6b33731336..372c3ac2bd 100644
--- a/third_party/abseil-cpp/absl/random/internal/randen_engine.h
+++ b/third_party/abseil-cpp/absl/random/internal/randen_engine.h
@@ -23,6 +23,7 @@
#include <limits>
#include <type_traits>
+#include "absl/base/internal/endian.h"
#include "absl/meta/type_traits.h"
#include "absl/random/internal/iostream_state_saver.h"
#include "absl/random/internal/randen.h"
@@ -76,7 +77,7 @@ class alignas(16) randen_engine {
impl_.Generate(state_);
}
- return state_[next_++];
+ return little_endian::ToHost(state_[next_++]);
}
template <class SeedSequence>
@@ -120,6 +121,13 @@ class alignas(16) randen_engine {
const size_t requested_entropy = (entropy_size == 0) ? 8u : entropy_size;
std::fill(std::begin(buffer) + requested_entropy, std::end(buffer), 0);
seq.generate(std::begin(buffer), std::begin(buffer) + requested_entropy);
+#ifdef ABSL_IS_BIG_ENDIAN
+ // Randen expects the seed buffer to be in Little Endian; reverse it on
+ // Big Endian platforms.
+ for (sequence_result_type& e : buffer) {
+ e = absl::little_endian::FromHost(e);
+ }
+#endif
// The Randen paper suggests preferentially initializing even-numbered
// 128-bit vectors of the randen state (there are 16 such vectors).
// The seed data is merged into the state offset by 128-bits, which
@@ -181,7 +189,8 @@ class alignas(16) randen_engine {
// In the case that `elem` is `uint8_t`, it must be cast to something
// larger so that it prints as an integer rather than a character. For
// simplicity, apply the cast all circumstances.
- os << static_cast<numeric_type>(elem) << os.fill();
+ os << static_cast<numeric_type>(little_endian::FromHost(elem))
+ << os.fill();
}
os << engine.next_;
return os;
@@ -200,7 +209,7 @@ class alignas(16) randen_engine {
// necessary to read a wider type and then cast it to uint8_t.
numeric_type value;
is >> value;
- elem = static_cast<result_type>(value);
+ elem = little_endian::ToHost(static_cast<result_type>(value));
}
is >> next;
if (is.fail()) {