From 94dc0387683b4a1fb6967c67403d9d1608ac3165 Mon Sep 17 00:00:00 2001
From: Tyler Karaszewski <tyler@expensify.com>
Date: Thu, 7 Dec 2023 16:40:39 -0700
Subject: [PATCH 1/3] Allocate when called, not at startup

---
 libstuff/SRandom.cpp | 19 ++++++++++++-------
 libstuff/SRandom.h   |  2 +-
 2 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/libstuff/SRandom.cpp b/libstuff/SRandom.cpp
index b6900dac6..baa2421d7 100644
--- a/libstuff/SRandom.cpp
+++ b/libstuff/SRandom.cpp
@@ -1,20 +1,25 @@
 #include "SRandom.h"
 
-#ifdef VALGRIND
-// random_device breaks valgrind.
-mt19937_64 SRandom::_generator = mt19937_64();
-#else
-mt19937_64 SRandom::_generator = mt19937_64(random_device()());
-#endif
-
 uniform_int_distribution<uint64_t> SRandom::_distribution64 = uniform_int_distribution<uint64_t>();
 
 uint64_t SRandom::limitedRand64(uint64_t minNum, uint64_t maxNum) {
      uniform_int_distribution<uint64_t> limitedRandom(minNum, maxNum);
+#ifdef VALGRIND
+    // random_device breaks valgrind.
+    mt19937_64 _generator = mt19937_64();
+#else
+    mt19937_64 _generator = mt19937_64(random_device()());
+#endif
      return limitedRandom(_generator);
 }
 
 uint64_t SRandom::rand64() {
+#ifdef VALGRIND
+    // random_device breaks valgrind.
+    mt19937_64 _generator = mt19937_64();
+#else
+    mt19937_64 _generator = mt19937_64(random_device()());
+#endif
     return _distribution64(_generator);
 }
 
diff --git a/libstuff/SRandom.h b/libstuff/SRandom.h
index a718a04cd..c23f0674c 100644
--- a/libstuff/SRandom.h
+++ b/libstuff/SRandom.h
@@ -11,8 +11,8 @@ class SRandom {
     static uint64_t rand64();
     static uint64_t limitedRand64(uint64_t min, uint64_t max);
     static string randStr(uint& length);
+    void init();
 
   private:
-    static mt19937_64 _generator;
     static uniform_int_distribution<uint64_t> _distribution64;
 };

From 61a65325127b1d8c91413876c3282d443ea6be5a Mon Sep 17 00:00:00 2001
From: Tyler Karaszewski <tyler@expensify.com>
Date: Thu, 7 Dec 2023 16:48:02 -0700
Subject: [PATCH 2/3] oops, was testing with this

---
 libstuff/SRandom.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/libstuff/SRandom.h b/libstuff/SRandom.h
index c23f0674c..1f1cba16e 100644
--- a/libstuff/SRandom.h
+++ b/libstuff/SRandom.h
@@ -11,7 +11,6 @@ class SRandom {
     static uint64_t rand64();
     static uint64_t limitedRand64(uint64_t min, uint64_t max);
     static string randStr(uint& length);
-    void init();
 
   private:
     static uniform_int_distribution<uint64_t> _distribution64;

From d51fa1f26a22f1666a4f349e2cef338b90b6a9bf Mon Sep 17 00:00:00 2001
From: Tyler Karaszewski <tyler@tylerkaraszewski.com>
Date: Fri, 8 Dec 2023 07:05:47 -0800
Subject: [PATCH 3/3] Revert "Allocate RNG when called, not at startup"

---
 libstuff/SRandom.cpp | 19 +++++++------------
 libstuff/SRandom.h   |  1 +
 2 files changed, 8 insertions(+), 12 deletions(-)

diff --git a/libstuff/SRandom.cpp b/libstuff/SRandom.cpp
index baa2421d7..b6900dac6 100644
--- a/libstuff/SRandom.cpp
+++ b/libstuff/SRandom.cpp
@@ -1,25 +1,20 @@
 #include "SRandom.h"
 
+#ifdef VALGRIND
+// random_device breaks valgrind.
+mt19937_64 SRandom::_generator = mt19937_64();
+#else
+mt19937_64 SRandom::_generator = mt19937_64(random_device()());
+#endif
+
 uniform_int_distribution<uint64_t> SRandom::_distribution64 = uniform_int_distribution<uint64_t>();
 
 uint64_t SRandom::limitedRand64(uint64_t minNum, uint64_t maxNum) {
      uniform_int_distribution<uint64_t> limitedRandom(minNum, maxNum);
-#ifdef VALGRIND
-    // random_device breaks valgrind.
-    mt19937_64 _generator = mt19937_64();
-#else
-    mt19937_64 _generator = mt19937_64(random_device()());
-#endif
      return limitedRandom(_generator);
 }
 
 uint64_t SRandom::rand64() {
-#ifdef VALGRIND
-    // random_device breaks valgrind.
-    mt19937_64 _generator = mt19937_64();
-#else
-    mt19937_64 _generator = mt19937_64(random_device()());
-#endif
     return _distribution64(_generator);
 }
 
diff --git a/libstuff/SRandom.h b/libstuff/SRandom.h
index 1f1cba16e..a718a04cd 100644
--- a/libstuff/SRandom.h
+++ b/libstuff/SRandom.h
@@ -13,5 +13,6 @@ class SRandom {
     static string randStr(uint& length);
 
   private:
+    static mt19937_64 _generator;
     static uniform_int_distribution<uint64_t> _distribution64;
 };