diff --git a/src/coreclr/jit/fgprofilesynthesis.cpp b/src/coreclr/jit/fgprofilesynthesis.cpp
index d76dcece8220da..2de615136cfeb4 100644
--- a/src/coreclr/jit/fgprofilesynthesis.cpp
+++ b/src/coreclr/jit/fgprofilesynthesis.cpp
@@ -1289,6 +1289,12 @@ void ProfileSynthesis::GaussSeidelSolver()
                 residual      = change;
                 residualBlock = block;
             }
+
+            if (newWeight >= maxCount)
+            {
+                JITDUMP("count overflow in " FMT_BB ": " FMT_WT "\n", block->bbNum, newWeight);
+                m_overflow = true;
+            }
         }
 
         // If there were no improper headers, we will have converged in one pass.
@@ -1312,6 +1318,11 @@ void ProfileSynthesis::GaussSeidelSolver()
             break;
         }
 
+        if (m_overflow)
+        {
+            break;
+        }
+
         // If we have been iterating for a bit, estimate the dominant GS
         // eigenvalue. (we might want to start with Jacobi iterations
         // to get the Jacobi eigenvalue instead).
diff --git a/src/coreclr/jit/fgprofilesynthesis.h b/src/coreclr/jit/fgprofilesynthesis.h
index c5e3883bdca000..216bd58297286a 100644
--- a/src/coreclr/jit/fgprofilesynthesis.h
+++ b/src/coreclr/jit/fgprofilesynthesis.h
@@ -51,6 +51,7 @@ class ProfileSynthesis
     static constexpr weight_t ilNextLikelihood   = 0.52;
     static constexpr weight_t loopBackLikelihood = 0.9;
     static constexpr weight_t loopExitLikelihood = 0.9;
+    static constexpr weight_t maxCount           = 1e12;
 
     void Run(ProfileSynthesisOption option);
 
@@ -84,6 +85,7 @@ class ProfileSynthesis
     unsigned               m_improperLoopHeaders       = 0;
     unsigned               m_cappedCyclicProbabilities = 0;
     bool                   m_approximate               = false;
+    bool                   m_overflow                  = false;
 };
 
 #endif // !_FGPROFILESYNTHESIS_H_