From 9aa80d33534a92704b9491a7d3e5e0cbc33870cf Mon Sep 17 00:00:00 2001
From: David Truby <david.truby@arm.com>
Date: Wed, 2 Oct 2019 16:58:11 +0100
Subject: [PATCH] [flang] Make the second argument to dist_schedule optional.

Original-commit: flang-compiler/f18@7ed2d0e3ec68f00c483d3107d0383a4f172d1feb
Reviewed-on: https://github.com/flang-compiler/f18/pull/772
Tree-same-pre-rewrite: false
---
 flang/lib/parser/openmp-grammar.h | 5 +++--
 flang/lib/parser/parse-tree.h     | 2 +-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/flang/lib/parser/openmp-grammar.h b/flang/lib/parser/openmp-grammar.h
index a7e71ec..b1bdb03 100644
--- a/flang/lib/parser/openmp-grammar.h
+++ b/flang/lib/parser/openmp-grammar.h
@@ -186,8 +186,9 @@ TYPE_PARSER("ALIGNED" >>
         construct<OmpClause>(parenthesized(Parser<OmpDependClause>{})) ||
     "DEVICE" >> construct<OmpClause>(construct<OmpClause::Device>(
                     parenthesized(scalarIntExpr))) ||
-    "DIST_SCHEDULE" >> construct<OmpClause>(construct<OmpClause::DistSchedule>(
-                           parenthesized("STATIC ," >> scalarIntExpr))) ||
+    "DIST_SCHEDULE" >>
+        construct<OmpClause>(construct<OmpClause::DistSchedule>(
+            parenthesized("STATIC" >> maybe("," >> scalarIntExpr)))) ||
     "FINAL" >> construct<OmpClause>(construct<OmpClause::Final>(
                    parenthesized(scalarLogicalExpr))) ||
     "FIRSTPRIVATE" >> construct<OmpClause>(construct<OmpClause::Firstprivate>(
diff --git a/flang/lib/parser/parse-tree.h b/flang/lib/parser/parse-tree.h
index 712b4c6..08d1360 100644
--- a/flang/lib/parser/parse-tree.h
+++ b/flang/lib/parser/parse-tree.h
@@ -3447,7 +3447,7 @@ struct OmpClause {
   WRAPPER_CLASS(Copyin, OmpObjectList);
   WRAPPER_CLASS(Copyprivate, OmpObjectList);
   WRAPPER_CLASS(Device, ScalarIntExpr);
-  WRAPPER_CLASS(DistSchedule, ScalarIntExpr);
+  WRAPPER_CLASS(DistSchedule, std::optional<ScalarIntExpr>);
   WRAPPER_CLASS(Final, ScalarLogicalExpr);
   WRAPPER_CLASS(Firstprivate, OmpObjectList);
   WRAPPER_CLASS(From, OmpObjectList);
-- 
2.7.4