Imported Upstream version 1.67.0upstream/1.67.0

1 files changed, 5 insertions, 1 deletions

diff --git a/boost/random/linear_congruential.hpp b/boost/random/linear_congruential.hpp
index de3a1d0749..22ade3f3db 100644
--- a/boost/random/linear_congruential.hpp
+++ b/boost/random/linear_congruential.hpp
@@ -124,8 +124,12 @@ public:
      * distinct seeds in the range [1,m) will leave the generator in distinct
      * states. If c is not zero, the range is [0,m).
      */
-    BOOST_RANDOM_DETAIL_ARITHMETIC_SEED(linear_congruential_engine, IntType, x0)
+    BOOST_RANDOM_DETAIL_ARITHMETIC_SEED(linear_congruential_engine, IntType, x0_)
     {
+        // Work around a msvc 12/14 optimizer bug, which causes
+        // the line _x = 1 to run unconditionally sometimes.
+        // Creating a local copy seems to make it work.
+        IntType x0 = x0_;
         // wrap _x if it doesn't fit in the destination
         if(modulus == 0) {
             _x = x0;