diff --git a/flang/runtime/connection.h b/flang/runtime/connection.h
--- a/flang/runtime/connection.h
+++ b/flang/runtime/connection.h
@@ -26,9 +26,10 @@
 // established in an OPEN statement.
 struct ConnectionAttributes {
   Access access{Access::Sequential}; // ACCESS='SEQUENTIAL', 'DIRECT', 'STREAM'
-  std::optional<std::int64_t> recordLength; // RECL= when fixed-length
   bool isUnformatted{false}; // FORM='UNFORMATTED'
   bool isUTF8{false}; // ENCODING='UTF-8'
+  bool isFixedRecordLength{false}; // RECL= on OPEN
+  std::optional<std::int64_t> recordLength; // RECL= or current record
 };
 
 struct ConnectionState : public ConnectionAttributes {
@@ -37,6 +38,12 @@
   void HandleAbsolutePosition(std::int64_t);
   void HandleRelativePosition(std::int64_t);
 
+  void BeginRecord() {
+    positionInRecord = 0;
+    furthestPositionInRecord = 0;
+    leftTabLimit.reset();
+  }
+
   // Positions in a record file (sequential or direct, not stream)
   std::int64_t currentRecordNumber{1}; // 1 is first
   std::int64_t positionInRecord{0}; // offset in current record
diff --git a/flang/runtime/internal-unit.cpp b/flang/runtime/internal-unit.cpp
--- a/flang/runtime/internal-unit.cpp
+++ b/flang/runtime/internal-unit.cpp
@@ -17,6 +17,7 @@
 template <Direction DIR>
 InternalDescriptorUnit<DIR>::InternalDescriptorUnit(
     Scalar scalar, std::size_t length) {
+  isFixedRecordLength = true;
   recordLength = length;
   endfileRecordNumber = 2;
   void *pointer{reinterpret_cast<void *>(const_cast<char *>(scalar))};
@@ -33,6 +34,7 @@
       terminator, that.SizeInBytes() <= d.SizeInBytes(maxRank, true, 0));
   new (&d) Descriptor{that};
   d.Check();
+  isFixedRecordLength = true;
   recordLength = d.ElementBytes();
   endfileRecordNumber = d.Elements() + 1;
 }
@@ -123,8 +125,7 @@
     }
   }
   ++currentRecordNumber;
-  positionInRecord = 0;
-  furthestPositionInRecord = 0;
+  BeginRecord();
   return true;
 }
 
@@ -132,8 +133,7 @@
 void InternalDescriptorUnit<DIR>::BackspaceRecord(IoErrorHandler &handler) {
   RUNTIME_CHECK(handler, currentRecordNumber > 1);
   --currentRecordNumber;
-  positionInRecord = 0;
-  furthestPositionInRecord = 0;
+  BeginRecord();
 }
 
 template class InternalDescriptorUnit<Direction::Output>;