diff --git a/code/AssetLib/M3D/m3d.h b/code/AssetLib/M3D/m3d.h
index 2d5b73a720..b82137d362 100644
--- a/code/AssetLib/M3D/m3d.h
+++ b/code/AssetLib/M3D/m3d.h
@@ -5578,9 +5578,9 @@ unsigned char *m3d_save(m3d_t *model, int quality, int flags, unsigned int *size
                         } else
                             out--;
                         break;
-                    case m3dpf_uint8: *out++ = m->prop[i].value.num; break;
+                    case m3dpf_uint8: *out++ = (uint8_t)m->prop[i].value.num; break;
                     case m3dpf_uint16:
-                        *((uint16_t *)out) = m->prop[i].value.num;
+                        *((uint16_t *)out) = (uint16_t)m->prop[i].value.num;
                         out += 2;
                         break;
                     case m3dpf_uint32:
@@ -5655,7 +5655,7 @@ unsigned char *m3d_save(m3d_t *model, int quality, int flags, unsigned int *size
                              face[i].data.normal[1] == M3D_UNDEF || face[i].data.normal[2] == M3D_UNDEF) ?
                                     0 :
                                     2);
-                *out++ = k;
+                *out++ = (uint8_t)k;
                 for (j = 0; j < 3; j++) {
                     out = _m3d_addidx(out, vi_s, vrtxidx[face[i].data.vertex[j]]);
                     if (k & 1)
diff --git a/code/AssetLib/glTF/glTFExporter.cpp b/code/AssetLib/glTF/glTFExporter.cpp
index b85affc083..110d2be4a9 100644
--- a/code/AssetLib/glTF/glTFExporter.cpp
+++ b/code/AssetLib/glTF/glTFExporter.cpp
@@ -536,10 +536,12 @@ void glTFExporter::ExportMeshes()
 
     // Variables needed for compression. BEGIN.
     // Indices, not pointers - because pointer to buffer is changing while writing to it.
+#ifdef ASSIMP_IMPORTER_GLTF_USE_OPEN3DGC
     size_t idx_srcdata_begin = 0; // Index of buffer before writing mesh data. Also, index of begin of coordinates array in buffer.
     size_t idx_srcdata_normal = SIZE_MAX;// Index of begin of normals array in buffer. SIZE_MAX - mean that mesh has no normals.
-    std::vector<size_t> idx_srcdata_tc;// Array of indices. Every index point to begin of texture coordinates array in buffer.
     size_t idx_srcdata_ind;// Index of begin of coordinates indices array in buffer.
+#endif
+    std::vector<size_t> idx_srcdata_tc;// Array of indices. Every index point to begin of texture coordinates array in buffer.
     bool comp_allow;// Point that data of current mesh can be compressed.
     // Variables needed for compression. END.
 
@@ -609,13 +611,17 @@ void glTFExporter::ExportMeshes()
 
 		/******************* Vertices ********************/
 		// If compression is used then you need parameters of uncompressed region: begin and size. At this step "begin" is stored.
+#ifdef ASSIMP_IMPORTER_GLTF_USE_OPEN3DGC
 		if(comp_allow) idx_srcdata_begin = b->byteLength;
+#endif
 
         Ref<Accessor> v = ExportData(*mAsset, meshId, b, aim->mNumVertices, aim->mVertices, AttribType::VEC3, AttribType::VEC3, ComponentType_FLOAT, BufferViewTarget_ARRAY_BUFFER);
 		if (v) p.attributes.position.push_back(v);
 
 		/******************** Normals ********************/
+#ifdef ASSIMP_IMPORTER_GLTF_USE_OPEN3DGC
 		if(comp_allow && (aim->mNormals != 0)) idx_srcdata_normal = b->byteLength;// Store index of normals array.
+#endif
 
 		Ref<Accessor> n = ExportData(*mAsset, meshId, b, aim->mNumVertices, aim->mNormals, AttribType::VEC3, AttribType::VEC3, ComponentType_FLOAT, BufferViewTarget_ARRAY_BUFFER);
 		if (n) p.attributes.normal.push_back(n);
@@ -640,7 +646,9 @@ void glTFExporter::ExportMeshes()
 		}
 
 		/*************** Vertices indices ****************/
+#ifdef ASSIMP_IMPORTER_GLTF_USE_OPEN3DGC
 		idx_srcdata_ind = b->byteLength;// Store index of indices array.
+#endif
 
 		if (aim->mNumFaces > 0) {
 			std::vector<IndicesType> indices;