diff --git a/flang/lib/Lower/OpenACC.cpp b/flang/lib/Lower/OpenACC.cpp
--- a/flang/lib/Lower/OpenACC.cpp
+++ b/flang/lib/Lower/OpenACC.cpp
@@ -671,9 +671,11 @@
                        &clause.u)) {
       genObjectList(privateClause->v, converter, semanticsContext, stmtCtx,
                     privateOperands);
+    } else if (std::get_if<Fortran::parser::AccClause::Reduction>(&clause.u)) {
+      // Reduction clause is left out for the moment as the clause will probably
+      // end up having its own operation.
+      TODO(clauseLocation, "OpenACC compute construct reduction lowering");
     }
-    // Reduction clause is left out for the moment as the clause will probably
-    // end up having its own operation.
   }
 
   // Prepare the operand segment size attribute and the operands value range.
@@ -715,6 +717,8 @@
     } else if (std::get_if<Fortran::parser::AccClause::Auto>(&clause.u)) {
       loopOp->setAttr(mlir::acc::LoopOp::getAutoAttrStrName(),
                       firOpBuilder.getUnitAttr());
+    } else if (std::get_if<Fortran::parser::AccClause::Reduction>(&clause.u)) {
+      TODO(currentLocation, "OpenACC loop reduction lowering");
     }
   }
   return loopOp;