diff --git a/ASTree.cpp b/ASTree.cpp
index 108e4e4..8776265 100644
--- a/ASTree.cpp
+++ b/ASTree.cpp
@@ -638,7 +638,10 @@ PycRef<ASTNode> BuildFromCode(PycRef<PycCode> code, PycModule* mod)
                 stack.pop();
                 PycRef<ASTNode> left = stack.top();
                 stack.pop();
-                stack.push(new ASTCompare(left, right, operand));
+                auto arg = operand;
+                if (mod->verCompare(3, 12) >= 0)
+                    arg >>= 4; // changed under GH-100923
+                stack.push(new ASTCompare(left, right, arg));
             }
             break;
         case Pyc::CONTAINS_OP_A:
diff --git a/bytecode.cpp b/bytecode.cpp
index 1dc9dc0..33c1abc 100644
--- a/bytecode.cpp
+++ b/bytecode.cpp
@@ -489,10 +489,15 @@ void bc_disasm(std::ostream& pyc_output, PycRef<PycCode> code, PycModule* mod,
                 }
                 break;
             case Pyc::COMPARE_OP_A:
-                if (static_cast<size_t>(operand) < cmp_strings_len)
-                    formatted_print(pyc_output, "%d (%s)", operand, cmp_strings[operand]);
-                else
-                    formatted_print(pyc_output, "%d (UNKNOWN)", operand);
+                {
+                    auto arg = operand;
+                    if (mod->verCompare(3, 12) >= 0)
+                        arg >>= 4; // changed under GH-100923
+                    if (static_cast<size_t>(arg) < cmp_strings_len)
+                        formatted_print(pyc_output, "%d (%s)", operand, cmp_strings[arg]);
+                    else
+                        formatted_print(pyc_output, "%d (UNKNOWN)", operand);
+                }
                 break;
             case Pyc::BINARY_OP_A:
                 if (static_cast<size_t>(operand) < binop_strings_len)