diff --git a/apps/sequence/sequence_context.h b/apps/sequence/sequence_context.h
index 16ddcdd9c..7ce0afd4c 100644
--- a/apps/sequence/sequence_context.h
+++ b/apps/sequence/sequence_context.h
@@ -48,8 +48,8 @@ public:
   const Poincare::Expression expressionForSymbol(const Poincare::Symbol & symbol) override {
     return m_parentContext->expressionForSymbol(symbol);
   }
-  void setExpressionForSymbolName(const Poincare::Expression & expression, const Poincare::Symbol & symbol, Poincare::Context & context) override {
-    m_parentContext->setExpressionForSymbolName(expression, symbol, context);
+  void setExpressionForSymbolName(const Poincare::Expression & expression, const char * symbolName, Poincare::Context & context) override {
+    m_parentContext->setExpressionForSymbolName(expression, symbolName, context);
   }
   template<typename T> T valueOfSequenceAtPreviousRank(int sequenceIndex, int rank) const {
     if (sizeof(T) == sizeof(float)) {
diff --git a/apps/shared/store_context.cpp b/apps/shared/store_context.cpp
index 1a131bd5f..8ec49e6cb 100644
--- a/apps/shared/store_context.cpp
+++ b/apps/shared/store_context.cpp
@@ -7,8 +7,8 @@ using namespace Poincare;
 
 namespace Shared {
 
-void StoreContext::setExpressionForSymbolName(const Expression & expression, const Symbol & symbol, Context & context) {
-  m_parentContext->setExpressionForSymbolName(expression, symbol, context);
+void StoreContext::setExpressionForSymbolName(const Expression & expression, const char * symbolName, Context & context) {
+  m_parentContext->setExpressionForSymbolName(expression, symbolName, context);
 }
 
 }
diff --git a/apps/shared/store_context.h b/apps/shared/store_context.h
index 549002c4f..f29471e7d 100644
--- a/apps/shared/store_context.h
+++ b/apps/shared/store_context.h
@@ -19,7 +19,7 @@ public:
   {}
   void setParentContext(Poincare::Context * parentContext) { m_parentContext = parentContext; }
   void setSeriesPairIndex(int j) { m_seriesPairIndex = j; }
-  void setExpressionForSymbolName(const Poincare::Expression & expression, const Poincare::Symbol & symbol, Poincare::Context & context) override;
+  void setExpressionForSymbolName(const Poincare::Expression & expression, const char * symbolName, Poincare::Context & context) override;
 protected:
   Shared::DoublePairStore * m_store;
   int m_seriesPairIndex;
diff --git a/apps/variable_box_controller.cpp b/apps/variable_box_controller.cpp
index b493925ce..16ed2e6c9 100644
--- a/apps/variable_box_controller.cpp
+++ b/apps/variable_box_controller.cpp
@@ -79,12 +79,12 @@ bool VariableBoxController::ContentViewController::handleEvent(Ion::Events::Even
   }
   if (event == Ion::Events::Backspace && m_currentPage != Page::RootMenu) {
     if (m_currentPage == Page::Scalar) {
-      const Symbol symbol('A'+selectedRow());
-      m_context->setExpressionForSymbolName(Expression(), symbol, *m_context);
+      const char symbolName[2] = {static_cast<char>('A'+selectedRow()), 0};
+      m_context->setExpressionForSymbolName(Expression(), symbolName, *m_context);
     }
     if (m_currentPage == Page::Matrix) {
-      const Symbol symbol = Symbol::matrixSymbol('0'+(char)selectedRow());
-      m_context->setExpressionForSymbolName(Expression(), symbol, *m_context);
+      const Symbol symbol = Symbol::matrixSymbol('0'+(char)selectedRow()); // TODO do not build an expression, just compute its name
+      m_context->setExpressionForSymbolName(Expression(), symbol.name(), *m_context);
       m_matrixLayouts[selectedRow()] = Layout();
     }
     m_selectableTableView.reloadData();
diff --git a/poincare/include/poincare/context.h b/poincare/include/poincare/context.h
index 544c6f7c6..bc84a0ecd 100644
--- a/poincare/include/poincare/context.h
+++ b/poincare/include/poincare/context.h
@@ -9,7 +9,7 @@ class Symbol;
 class Context {
 public:
   virtual const Expression expressionForSymbol(const Symbol & symbol) = 0;
-  virtual void setExpressionForSymbolName(const Expression & expression, const Symbol & symbol, Context & context) = 0;
+  virtual void setExpressionForSymbolName(const Expression & expression, const char * symbolName, Context & context) = 0;
 };
 
 }
diff --git a/poincare/include/poincare/global_context.h b/poincare/include/poincare/global_context.h
index 965165c3d..998a2a68a 100644
--- a/poincare/include/poincare/global_context.h
+++ b/poincare/include/poincare/global_context.h
@@ -17,7 +17,7 @@ public:
   /* The expression recorded in global context is already a expression.
    * Otherwise, we would need the context and the angle unit to evaluate it */
   const Expression expressionForSymbol(const Symbol & symbol) override;
-  void setExpressionForSymbolName(const Expression & expression, const Symbol & symbol, Context & context) override;
+  void setExpressionForSymbolName(const Expression & expression, const char * symbolName, Context & context) override;
   static constexpr uint16_t k_maxNumberOfExpressions = 36;
   static constexpr uint16_t k_maxNumberOfFunctions = 10;
   //TODO static constexpr uint16_t k_maxNumberOfSequences = 10;
diff --git a/poincare/include/poincare/variable_context.h b/poincare/include/poincare/variable_context.h
index 616cb2912..4f1e1033a 100644
--- a/poincare/include/poincare/variable_context.h
+++ b/poincare/include/poincare/variable_context.h
@@ -13,7 +13,7 @@ public:
   void setApproximationForVariable(T value);
 
   // Context
-  void setExpressionForSymbolName(const Expression & expression, const Symbol & symbol, Context & context) override;
+  void setExpressionForSymbolName(const Expression & expression, const char * symbolName, Context & context) override;
   const Expression expressionForSymbol(const Symbol & symbol) override;
 
 private:
diff --git a/poincare/src/global_context.cpp b/poincare/src/global_context.cpp
index 7d6a192a6..43c76c323 100644
--- a/poincare/src/global_context.cpp
+++ b/poincare/src/global_context.cpp
@@ -23,16 +23,16 @@ const Expression GlobalContext::expressionForSymbol(const Symbol & symbol) {
   return ExpressionForRecord(RecordWithName(symbol.name()));
 }
 
-void GlobalContext::setExpressionForSymbolName(const Expression & expression, const Symbol & symbol, Context & context) {
+void GlobalContext::setExpressionForSymbolName(const Expression & expression, const char * symbolName, Context & context) {
   /* If the new expression contains the symbol, replace it because it will be
    * destroyed afterwards (to be able to do A+2->A) */
-  Ion::Storage::Record record = RecordWithName(symbol.name());
+  Ion::Storage::Record record = RecordWithName(symbolName);
   Expression e = ExpressionForRecord(record);
-  Expression finalExpression = expression.clone().replaceSymbolWithExpression(symbol.name(), e);
+  Expression finalExpression = expression.clone().replaceSymbolWithExpression(symbolName, e);
   // Delete any record with same name (as it is going to be overriden)
   record.destroy();
 
-  Ion::Storage::Record::ErrorStatus err = Ion::Storage::sharedStorage()->createRecordWithExtension(symbol.name(), ExtensionForExpression(finalExpression), finalExpression.addressInPool(), finalExpression.size());
+  Ion::Storage::Record::ErrorStatus err = Ion::Storage::sharedStorage()->createRecordWithExtension(symbolName, ExtensionForExpression(finalExpression), finalExpression.addressInPool(), finalExpression.size());
   if (err != Ion::Storage::Record::ErrorStatus::None) {
     assert(err == Ion::Storage::Record::ErrorStatus::NotEnoughSpaceAvailable);
     // TODO: return false to set flag that the file system is full?
diff --git a/poincare/src/store.cpp b/poincare/src/store.cpp
index 87725b566..c30a6be4f 100644
--- a/poincare/src/store.cpp
+++ b/poincare/src/store.cpp
@@ -33,7 +33,7 @@ Layout StoreNode::createLayout(Preferences::PrintFloatMode floatDisplayMode, int
 template<typename T>
 Evaluation<T> StoreNode::templatedApproximate(Context& context, Preferences::AngleUnit angleUnit) const {
   Store s(this);
-  context.setExpressionForSymbolName(s.value(), s.symbol(), context);
+  context.setExpressionForSymbolName(s.value(), s.symbol().name(), context);
   if (context.expressionForSymbol(s.symbol()).isUninitialized()) {
     return Complex<T>::Undefined();
   }
@@ -41,7 +41,7 @@ Evaluation<T> StoreNode::templatedApproximate(Context& context, Preferences::Ang
 }
 
 Expression Store::shallowReduce(Context & context, Preferences::AngleUnit angleUnit) {
-  context.setExpressionForSymbolName(value(), symbol(), context);
+  context.setExpressionForSymbolName(value(), symbol().name(), context);
   Expression c1 = childAtIndex(1);
   replaceWithInPlace(c1);
   return c1.shallowReduce(context, angleUnit);
diff --git a/poincare/src/variable_context.cpp b/poincare/src/variable_context.cpp
index 12dcf4021..49dd041c0 100644
--- a/poincare/src/variable_context.cpp
+++ b/poincare/src/variable_context.cpp
@@ -20,14 +20,14 @@ void VariableContext<T>::setApproximationForVariable(T value) {
 }
 
 template<typename T>
-void VariableContext<T>::setExpressionForSymbolName(const Expression & expression, const Symbol & symbol, Context & context) {
-  if (strcmp(symbol.name(), m_name) == 0) {
+void VariableContext<T>::setExpressionForSymbolName(const Expression & expression, const char * symbolName, Context & context) {
+  if (strcmp(symbolName, m_name) == 0) {
     if (expression.isUninitialized()) {
       return;
     }
     m_value = Float<T>(expression.approximateToScalar<T>(context, Preferences::sharedPreferences()->angleUnit()));
   } else {
-    m_parentContext->setExpressionForSymbolName(expression, symbol, context);
+    m_parentContext->setExpressionForSymbolName(expression, symbolName, context);
   }
 }