diff --git a/code/IFCGeometry.cpp b/code/IFCGeometry.cpp
index 908f5e065..332b2af56 100644
--- a/code/IFCGeometry.cpp
+++ b/code/IFCGeometry.cpp
@@ -330,7 +330,11 @@ void ProcessSweptDiskSolid(const IfcSweptDiskSolid solid, TempMesh& result, Conv
     const unsigned int cnt_segments = conv.settings.cylindricalTessellation;
     const IfcFloat deltaAngle = AI_MATH_TWO_PI/cnt_segments;
 
-    const size_t samples = curve->EstimateSampleCount(solid.StartParam,solid.EndParam);
+	TempMesh temp;
+	curve->SampleDiscrete(temp, solid.StartParam, solid.EndParam);
+	const std::vector<IfcVector3>& curve_points = temp.verts;
+
+    const size_t samples = curve_points.size();
 
     result.verts.reserve(cnt_segments * samples * 4);
     result.vertcnt.reserve((cnt_segments - 1) * samples);
@@ -338,10 +342,6 @@ void ProcessSweptDiskSolid(const IfcSweptDiskSolid solid, TempMesh& result, Conv
     std::vector<IfcVector3> points;
     points.reserve(cnt_segments * samples);
 
-    TempMesh temp;
-    curve->SampleDiscrete(temp,solid.StartParam,solid.EndParam);
-    const std::vector<IfcVector3>& curve_points = temp.verts;
-
     if(curve_points.empty()) {
         IFCImporter::LogWarn("curve evaluation yielded no points (IfcSweptDiskSolid)");
         return;
diff --git a/code/IFCReaderGen1.cpp b/code/IFCReaderGen1.cpp
index bd526d454..622976819 100644
--- a/code/IFCReaderGen1.cpp
+++ b/code/IFCReaderGen1.cpp
@@ -2652,6 +2652,7 @@ template <> size_t GenericFill<IfcNamedUnit>(const DB& db, const LIST& params, I
 	size_t base = 0;
 	if (params.GetSize() < 2) { throw STEP::TypeError("expected 2 arguments to IfcNamedUnit"); }    do { // convert the 'Dimensions' argument
         std::shared_ptr<const DataType> arg = params[base++];
+		if (dynamic_cast<const UNSET*>(&*arg)) break;
         if (dynamic_cast<const ISDERIVED*>(&*arg)) { in->ObjectHelper<Assimp::IFC::IfcNamedUnit,2>::aux_is_derived[0]=true; break; }
         try { GenericConvert( in->Dimensions, arg, db ); break; } 
         catch (const TypeError& t) { throw TypeError(t.what() + std::string(" - expected argument 0 to IfcNamedUnit to be a `IfcDimensionalExponents`")); }