From 32fee1944772ba98f2c181e0a90221c09def78a7 Mon Sep 17 00:00:00 2001
From: Stefan Weil <sw@weilnetz.de>
Date: Fri, 22 Nov 2024 21:29:57 +0100
Subject: [PATCH] Fix linear congruential random number generator

Fixes: #4146, #4148, #4270
Fixes: 2252936fc801 ("Use linear congruential random number generator [...]")
Signed-off-by: Stefan Weil <sw@weilnetz.de>
---
 src/ccutil/helpers.h | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/ccutil/helpers.h b/src/ccutil/helpers.h
index 21241502..20a48201 100644
--- a/src/ccutil/helpers.h
+++ b/src/ccutil/helpers.h
@@ -68,7 +68,9 @@ inline const std::vector<std::string> split(const std::string &s, char c) {
   return v;
 }
 
-// A simple linear congruential random number generator.
+// A simple linear congruential random number generator,
+// using Knuth's constants from:
+// http://en.wikipedia.org/wiki/Linear_congruential_generator.
 class TRand {
 public:
   // Sets the seed to the given value.
@@ -95,7 +97,10 @@ public:
   }
 
 private:
-  std::minstd_rand e;
+  std::linear_congruential_engine<std::uint_fast32_t,
+                                  6364136223846793005ULL,
+                                  1442695040888963407ULL,
+                                  UINT64_MAX> e;
 };
 
 // Remove newline (if any) at the end of the string.