diff --git a/sources/qetgraphicsitem/dynamicelementtextitem.cpp b/sources/qetgraphicsitem/dynamicelementtextitem.cpp
index a9af725ae..8cd32830a 100644
--- a/sources/qetgraphicsitem/dynamicelementtextitem.cpp
+++ b/sources/qetgraphicsitem/dynamicelementtextitem.cpp
@@ -30,6 +30,7 @@
 #include <QTimer>
 #include <QDomDocument>
 #include <QDomElement>
+#include <QtCore/qnumeric.h>
 #include <QGraphicsSceneMouseEvent>
 
 /**
@@ -221,8 +222,16 @@ void DynamicElementTextItem::fromXml(const QDomElement &dom_elmt)
 		//Force the update of the displayed text
 	setTextFrom(m_text_from);
 	
-	QGraphicsTextItem::setPos(dom_elmt.attribute("x", QString::number(0)).toDouble(),
-							  dom_elmt.attribute("y", QString::number(0)).toDouble());
+		//QString::toDouble() accepts "nan"/"inf"/"-inf" as a successful
+		//conversion, so a corrupted or hand-edited file can hand this a
+		//non-finite position -- fall back to 0 the same way a missing
+		//attribute already does, rather than letting it reach the scene
+		//(see the matching comment in Element::valideXml(), the fromXml()
+		//gate a plain element's position goes through; this text item has
+		//no such gate to reject the whole item at, so it clamps instead).
+	double x = dom_elmt.attribute("x", QString::number(0)).toDouble();
+	double y = dom_elmt.attribute("y", QString::number(0)).toDouble();
+	QGraphicsTextItem::setPos(qIsFinite(x) ? x : 0, qIsFinite(y) ? y : 0);
 }
 
 /**
diff --git a/sources/qetgraphicsitem/element.cpp b/sources/qetgraphicsitem/element.cpp
index 23c9eda42..14b3a8f4f 100644
--- a/sources/qetgraphicsitem/element.cpp
+++ b/sources/qetgraphicsitem/element.cpp
@@ -53,6 +53,7 @@ static const QString plcTerminalKeys[] = {
 #include <QDebug>
 
 #include <QDomElement>
+#include <QtCore/qnumeric.h>
 #include <utility>
 
 class ElementXmlRetroCompatibility
@@ -699,11 +700,16 @@ bool Element::valideXml(QDomElement &e)
 	}
 
 	bool conv_ok;
-	e.attribute(QStringLiteral("x")).toDouble(&conv_ok);
-	if (!conv_ok) return(false);
+		//QString::toDouble() accepts "nan"/"inf"/"-inf" and reports a
+		//successful conversion for them, so conv_ok alone doesn't reject a
+		//non-finite coordinate. A NaN position reaching the scene can hang
+		//QGraphicsScene::addItem() forever inside Qt's own polygon-clipping
+		//code when an existing conductor's collision test runs against it.
+	double x = e.attribute(QStringLiteral("x")).toDouble(&conv_ok);
+	if (!conv_ok || !qIsFinite(x)) return(false);
 
-	e.attribute(QStringLiteral("y")).toDouble(&conv_ok);
-	if (!conv_ok) return(false);
+	double y = e.attribute(QStringLiteral("y")).toDouble(&conv_ok);
+	if (!conv_ok || !qIsFinite(y)) return(false);
 
 	return(true);
 }
diff --git a/sources/qetgraphicsitem/terminal.cpp b/sources/qetgraphicsitem/terminal.cpp
index ec862b39c..aa2b3024f 100644
--- a/sources/qetgraphicsitem/terminal.cpp
+++ b/sources/qetgraphicsitem/terminal.cpp
@@ -25,6 +25,7 @@
 #include "../qetgraphicsitem/element.h"
 #include "conductortextitem.h"
 
+#include <QtCore/qnumeric.h>
 #include <utility>
 
 QColor Terminal::neutralColor      = QColor(Qt::blue);
@@ -741,13 +742,17 @@ bool Terminal::valideXml(QDomElement &terminal)
 	if (!terminal.hasAttribute("orientation")) return(false);
 
 	bool conv_ok;
+		//QString::toDouble() accepts "nan"/"inf"/"-inf" and reports a
+		//successful conversion for them, so conv_ok alone doesn't reject a
+		//non-finite coordinate -- see the matching comment in
+		//Element::valideXml().
 	// parse l'abscisse
-	terminal.attribute("x").toDouble(&conv_ok);
-	if (!conv_ok) return(false);
+	double x = terminal.attribute("x").toDouble(&conv_ok);
+	if (!conv_ok || !qIsFinite(x)) return(false);
 
 	// parse l'ordonnee
-	terminal.attribute("y").toDouble(&conv_ok);
-	if (!conv_ok) return(false);
+	double y = terminal.attribute("y").toDouble(&conv_ok);
+	if (!conv_ok || !qIsFinite(y)) return(false);
 
 	// parse l'id
 	terminal.attribute("id").toInt(&conv_ok);