From https://gitlab.kitware.com/vtk/vtk/-/commit/0322b938968eebee585ad7efb93bbdade7106355

https://bugs.gentoo.org/863038
https://gitlab.kitware.com/vtk/vtk/-/issues/18638

From: Aron Helser <aron.helser@kitware.com>
Date: Mon, 15 Aug 2022 10:06:13 -0400
Subject: [PATCH 16/30] Change or scope struct names to avoid conflicts.

(cherry picked from commit b79eb46bf5a4277cafc1ed2bd47fd3ffc28a5b3f)
--- a/IO/AMR/vtkAMRFlashReader.cxx
+++ b/IO/AMR/vtkAMRFlashReader.cxx
@@ -153,7 +153,7 @@ void vtkAMRFlashReader::ComputeStats(
 
   for (int i = 0; i < internal->NumberOfBlocks; ++i)
   {
-    Block& theBlock = internal->Blocks[i];
+    FlashReaderBlock& theBlock = internal->Blocks[i];
     double* gridMin = theBlock.MinBounds;
     if (gridMin[0] < min[0])
     {
@@ -193,7 +193,7 @@ int vtkAMRFlashReader::FillMetaData()
 
   for (int i = 0; i < this->Internal->NumberOfBlocks; ++i)
   {
-    Block& theBlock = this->Internal->Blocks[i];
+    FlashReaderBlock& theBlock = this->Internal->Blocks[i];
 
     // Start numbering levels from 0!
     int level = this->Internal->Blocks[i].Level - 1;
--- a/IO/AMR/vtkAMRFlashReaderInternal.cxx
+++ b/IO/AMR/vtkAMRFlashReaderInternal.cxx
@@ -692,7 +692,7 @@ void vtkFlashReaderInternal::GetBlockMinMaxGlobalDivisionIds()
 
   for (int b = 0; b < this->NumberOfBlocks; b++)
   {
-    Block& B = this->Blocks[b];
+    FlashReaderBlock& B = this->Blocks[b];
 
     for (int d = 0; d < 3; d++)
     {
--- a/IO/AMR/vtkAMRFlashReaderInternal.h
+++ b/IO/AMR/vtkAMRFlashReaderInternal.h
@@ -74,7 +74,7 @@ typedef struct tagFlashReaderSimulationParameters
   double RedShift;
 } FlashReaderSimulationParameters;
 
-typedef struct tagBlock
+typedef struct tagFlashReaderBlock
 {
   int Index;                   // Id of the block
   int Level;                   // LOD level
@@ -88,7 +88,7 @@ typedef struct tagBlock
   double Center[3];            // center of the block
   double MinBounds[3];         // lower left  of the bounding box
   double MaxBounds[3];         // upper right of the bounding box
-} Block;
+} FlashReaderBlock;
 
 typedef struct tagFlashReaderSimulationInformation
 {
@@ -152,7 +152,7 @@ public:
   FlashReaderSimulationInformation SimulationInformation; // CFD simulation
 
   // blocks
-  std::vector<Block> Blocks;
+  std::vector<FlashReaderBlock> Blocks;
   std::vector<int> LeafBlocks;
   std::vector<std::string> AttributeNames;
 
--- a/IO/AMR/vtkAMRVelodyneReader.cxx
+++ b/IO/AMR/vtkAMRVelodyneReader.cxx
@@ -219,7 +219,7 @@ int vtkAMRVelodyneReader::FillMetaData()
   double spacing[3];
   for (int i = 0; i < this->Internal->nBlocks; i++)
   {
-    Block& theBlock = this->Internal->Blocks[i];
+    vtkAMRVelodyneReaderInternal::Block& theBlock = this->Internal->Blocks[i];
     int level = theBlock.Level;
     int id = theBlock.Index;
     CalculateBlockDims(this->Internal->blockDims.data(), theBlock.isFull, dims);
@@ -243,7 +243,7 @@ vtkUniformGrid* vtkAMRVelodyneReader::GetAMRGrid(const int blockIdx)
   {
     return nullptr;
   }
-  Block& theBlock = this->Internal->Blocks[blockIdx];
+  vtkAMRVelodyneReaderInternal::Block& theBlock = this->Internal->Blocks[blockIdx];
   int dims[3];
   CalculateBlockDims(this->Internal->blockDims.data(), theBlock.isFull, dims);
   vtkUniformGrid* ug = vtkUniformGrid::New();
--- a/IO/AMR/vtkAMRVelodyneReaderInternal.h
+++ b/IO/AMR/vtkAMRVelodyneReaderInternal.h
@@ -48,24 +48,20 @@
 //================================================================================
 //                          INTERNAL VELODYNE READER
 //================================================================================
-typedef struct tagVelodyneSimParameters
-{
-  double Time;
-  int CycleTime;
-} VelodneSimParameters;
 
-typedef struct tagBlock
-{
-  int Index;
-  int dSetLoc;
-  int Level;
-  double Origin[3];
-  bool isFull;
-  bool isLeaf;
-} Block;
 class vtkAMRVelodyneReaderInternal
 {
 public:
+  typedef struct tagVelodyneBlock
+  {
+    int Index;
+    int dSetLoc;
+    int Level;
+    double Origin[3];
+    bool isFull;
+    bool isLeaf;
+  } Block;
+
   vtkAMRVelodyneReaderInternal();
   ~vtkAMRVelodyneReaderInternal();
   void SetFileName(VTK_FILEPATH VTK_FUTURE_CONST char* fileName);