From 14c7754a35da9bf6b346e2a6ce4b3d8c3b00b434 Mon Sep 17 00:00:00 2001
From: Jean Perier <jperier@nvidia.com>
Date: Thu, 31 Mar 2022 10:54:15 +0200
Subject: [PATCH] [flang] Skip `D` when including D debug line

When including debug lines as code, the `D` should be considered as
a white space. Currently an error was raised about bad labels because
it the `D` remained a `D` when considering the source line as code.

Differential Revision: https://reviews.llvm.org/D122711
---
 flang/lib/Parser/prescan.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/flang/lib/Parser/prescan.cpp b/flang/lib/Parser/prescan.cpp
index b4b8a17341f7..17fc090c8c9c 100644
--- a/flang/lib/Parser/prescan.cpp
+++ b/flang/lib/Parser/prescan.cpp
@@ -144,6 +144,10 @@ void Prescanner::Statement() {
   case LineClassification::Kind::Source:
     BeginStatementAndAdvance();
     if (inFixedForm_) {
+      if (features_.IsEnabled(LanguageFeature::OldDebugLines) &&
+          (*at_ == 'D' || *at_ == 'd')) {
+        NextChar();
+      }
       LabelField(tokens);
     } else if (skipLeadingAmpersand_) {
       skipLeadingAmpersand_ = false;