From 20093668199fb585c9e1446ec5a711480e6c5d9f Mon Sep 17 00:00:00 2001
From: Matt Rolchigo <rolchigomr@ornl.gov>
Date: Fri, 16 Jan 2026 10:12:10 -0500
Subject: [PATCH] Avoid storing std::string variables in a class accessed on
 device

---
 applications/SingleLayer.cpp     |  2 +-
 src/Finch_Run.hpp                |  4 ++--
 src/Finch_SolidificationData.hpp | 15 ++++++---------
 3 files changed, 9 insertions(+), 12 deletions(-)

diff --git a/applications/SingleLayer.cpp b/applications/SingleLayer.cpp
index 77c59de..d2a7ae0 100644
--- a/applications/SingleLayer.cpp
+++ b/applications/SingleLayer.cpp
@@ -49,7 +49,7 @@ void run( int argc, char* argv[] )
     app.run( exec_space(), db, grid, beam, fd );
 
     // Write the temperature data used by ExaCA/other post-processing
-    app.writeSolidificationData( grid.getComm() );
+    app.writeSolidificationData( db.sampling, grid.getComm() );
     app.getLowerSolidificationDataBounds( grid.getComm() );
     app.getUpperSolidificationDataBounds( grid.getComm() );
 }
diff --git a/src/Finch_Run.hpp b/src/Finch_Run.hpp
index 8b433f7..3dc1b39 100644
--- a/src/Finch_Run.hpp
+++ b/src/Finch_Run.hpp
@@ -108,9 +108,9 @@ class Layer
 
     auto getSolidificationData() { return solidification_data_.get(); }
 
-    auto writeSolidificationData( MPI_Comm comm )
+    auto writeSolidificationData( Sampling sampling_inputs, MPI_Comm comm )
     {
-        return solidification_data_.write( comm );
+        return solidification_data_.write( sampling_inputs, comm );
     }
 
     [[deprecated( "Use of getLowerSolidificationDataBounds() without a "
diff --git a/src/Finch_SolidificationData.hpp b/src/Finch_SolidificationData.hpp
index b1a2457..ecc3c33 100644
--- a/src/Finch_SolidificationData.hpp
+++ b/src/Finch_SolidificationData.hpp
@@ -49,12 +49,10 @@ class SolidificationData
   private:
     // Needed for file output
     int mpi_rank_;
-    std::string folder_name_;
     double liquidus_;
     double dt_;
     double cell_size_;
     bool enabled_;
-    std::string format_;
 
     view_int count;
 
@@ -72,12 +70,10 @@ class SolidificationData
     // constructor
     SolidificationData( const Inputs& inputs, Grid<memory_space>& grid )
         : mpi_rank_( grid.comm_rank )
-        , folder_name_( inputs.sampling.directory_name )
         , liquidus_( inputs.properties.liquidus )
         , dt_( inputs.time.time_step )
         , cell_size_( inputs.space.cell_size )
         , enabled_( inputs.sampling.enabled )
-        , format_( inputs.sampling.format )
     {
         count = view_int( "count", 1 );
 
@@ -224,7 +220,7 @@ class SolidificationData
     }
 
     // Write the solidification data to separate files for each MPI rank
-    void write( MPI_Comm comm )
+    void write( Sampling sampling_inputs, MPI_Comm comm )
     {
         if ( !enabled_ )
         {
@@ -241,13 +237,14 @@ class SolidificationData
             Kokkos::create_mirror_view_and_copy( Kokkos::HostSpace(), count );
 
         // create directory is not present, otherwise overwrite existing files
-        if ( mkdir( folder_name_.c_str(), 0777 ) != -1 )
+        if ( mkdir( sampling_inputs.directory_name.c_str(), 0777 ) != -1 )
         {
-            std::cout << "Creating directory: " << folder_name_ << std::endl;
+            std::cout << "Creating directory: "
+                      << sampling_inputs.directory_name << std::endl;
         }
 
         std::ofstream fout;
-        std::string filename( folder_name_ + "/data_" +
+        std::string filename( sampling_inputs.directory_name + "/data_" +
                               std::to_string( mpi_rank_ ) + ".csv" );
 
         fout.open( filename );
@@ -259,7 +256,7 @@ class SolidificationData
                  << events_host( n, 2 ) << "," << events_host( n, 3 ) << ","
                  << events_host( n, 4 ) << "," << events_host( n, 5 );
 
-            if ( format_ == "default" )
+            if ( sampling_inputs.format == "default" )
             {
                 fout << "," << events_host( n, 6 ) << "," << events_host( n, 7 )
                      << "," << events_host( n, 8 );