diff --git a/eeschema/tools/symbol_editor_edit_tool.cpp b/eeschema/tools/symbol_editor_edit_tool.cpp
index c8841533ed..e0f81c08ca 100644
--- a/eeschema/tools/symbol_editor_edit_tool.cpp
+++ b/eeschema/tools/symbol_editor_edit_tool.cpp
@@ -275,7 +275,7 @@ int SYMBOL_EDITOR_EDIT_TOOL::DoDelete( const TOOL_EVENT& aEvent )
             // in different units are also removed.  But only one pin per unit (matching)
             if( m_frame->SynchronizePins() )
             {
-                std::vector<bool> got_unit( symbol->GetUnitCount() );
+                std::vector<bool> got_unit( symbol->GetUnitCount() + 1 );
 
                 got_unit[pin->GetUnit()] = true;
 
diff --git a/eeschema/tools/symbol_editor_move_tool.cpp b/eeschema/tools/symbol_editor_move_tool.cpp
index 0898e1e0ae..20caf6a45b 100644
--- a/eeschema/tools/symbol_editor_move_tool.cpp
+++ b/eeschema/tools/symbol_editor_move_tool.cpp
@@ -156,7 +156,7 @@ int SYMBOL_EDITOR_MOVE_TOOL::Main( const TOOL_EVENT& aEvent )
                         {
                             LIB_PIN* cur_pin = static_cast<LIB_PIN*>( lib_item );
                             LIB_SYMBOL* symbol = m_frame->GetCurSymbol();
-                            std::vector<bool> got_unit( symbol->GetUnitCount() );
+                            std::vector<bool> got_unit( symbol->GetUnitCount() + 1 );
 
                             got_unit[cur_pin->GetUnit()] = true;
 
diff --git a/eeschema/tools/symbol_editor_pin_tool.cpp b/eeschema/tools/symbol_editor_pin_tool.cpp
index 38c47715eb..cfc18f7911 100644
--- a/eeschema/tools/symbol_editor_pin_tool.cpp
+++ b/eeschema/tools/symbol_editor_pin_tool.cpp
@@ -142,7 +142,7 @@ bool SYMBOL_EDITOR_PIN_TOOL::EditPinProperties( LIB_PIN* aPin )
         // a pin can have a unit id = 0 (common to all units) to unit count
         // So we need a buffer size = GetUnitCount()+1 to store a value in a vector
         // when using the unit id of a pin as index
-        std::vector<bool> got_unit( aPin->GetParent()->GetUnitCount()+1 );
+        std::vector<bool> got_unit( aPin->GetParent()->GetUnitCount() + 1 );
 
         got_unit[static_cast<size_t>(aPin->GetUnit())] = true;