erc.cpp

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/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2015 Jean-Pierre Charras, jp.charras at wanadoo.fr
 * Copyright (C) 2011 Wayne Stambaugh <[email protected]>
 * Copyright (C) 1992-2021 KiCad Developers, see AUTHORS.txt for contributors.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, you may find one here:
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * or you may search the http://www.gnu.org website for the version 2 license,
 * or you may write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
 */

#include "connection_graph.h"
#include <common.h> // for ExpandEnvVarSubstitutions
#include <erc.h>
#include <string_utils.h>
#include <lib_pin.h>
#include <sch_edit_frame.h>
#include <sch_marker.h>
#include <sch_reference_list.h>
#include <sch_sheet.h>
#include <sch_sheet_pin.h>
#include <schematic.h>
#include <drawing_sheet/ds_draw_item.h>
#include <drawing_sheet/ds_proxy_view_item.h>
#include <wx/ffile.h>


/* ERC tests :
 * 1 - conflicts between connected pins ( example: 2 connected outputs )
 * 2 - minimal connections requirements ( 1 input *must* be connected to an
 * output, or a passive pin )
 */

/*
 * Minimal ERC requirements:
 * All pins *must* be connected (except ELECTRICAL_PINTYPE::PT_NC).
 * When a pin is not connected in schematic, the user must place a "non
 * connected" symbol to this pin.
 * This ensures a forgotten connection will be detected.
 */

// Messages for matrix rows:
const wxString CommentERC_H[] =
{
 _( "Input Pin" ),
 _( "Output Pin" ),
 _( "Bidirectional Pin" ),
 _( "Tri-State Pin" ),
 _( "Passive Pin" ),
 _( "Free Pin" ),
 _( "Unspecified Pin" ),
 _( "Power Input Pin" ),
 _( "Power Output Pin" ),
 _( "Open Collector" ),
 _( "Open Emitter" ),
 _( "No Connection" )
};

// Messages for matrix columns
const wxString CommentERC_V[] =
{
 _( "Input Pin" ),
 _( "Output Pin" ),
 _( "Bidirectional Pin" ),
 _( "Tri-State Pin" ),
 _( "Passive Pin" ),
 _( "Free Pin" ),
 _( "Unspecified Pin" ),
 _( "Power Input Pin" ),
 _( "Power Output Pin" ),
 _( "Open Collector" ),
 _( "Open Emitter" ),
 _( "No Connection" )
};


// List of pin types that are considered drivers for usual input pins
// i.e. pin type = ELECTRICAL_PINTYPE::PT_INPUT, but not PT_POWER_IN
// that need only a PT_POWER_OUT pin type to be driven
const std::set<ELECTRICAL_PINTYPE> DrivingPinTypes =
 {
 ELECTRICAL_PINTYPE::PT_OUTPUT,
 ELECTRICAL_PINTYPE::PT_POWER_OUT,
 ELECTRICAL_PINTYPE::PT_PASSIVE,
 ELECTRICAL_PINTYPE::PT_TRISTATE,
 ELECTRICAL_PINTYPE::PT_BIDI
 };

// List of pin types that are considered drivers for power pins
// In fact only a ELECTRICAL_PINTYPE::PT_POWER_OUT pin type can drive
// power input pins
const std::set<ELECTRICAL_PINTYPE> DrivingPowerPinTypes =
 {
 ELECTRICAL_PINTYPE::PT_POWER_OUT
 };

// List of pin types that require a driver elsewhere on the net
const std::set<ELECTRICAL_PINTYPE> DrivenPinTypes =
 {
 ELECTRICAL_PINTYPE::PT_INPUT,
 ELECTRICAL_PINTYPE::PT_POWER_IN
 };

int ERC_TESTER::TestDuplicateSheetNames( bool aCreateMarker )
{
 SCH_SCREEN* screen;
 int err_count = 0;

 SCH_SCREENS screenList( m_schematic->Root() );

 for( screen = screenList.GetFirst(); screen != nullptr; screen = screenList.GetNext() )
 {
 std::vector<SCH_SHEET*> list;

 for( SCH_ITEM* item : screen->Items().OfType( SCH_SHEET_T ) )
 list.push_back( static_cast<SCH_SHEET*>( item ) );

 for( size_t i = 0; i < list.size(); i++ )
 {
 SCH_SHEET* sheet = list[i];

 for( size_t j = i + 1; j < list.size(); j++ )
 {
 SCH_SHEET* test_item = list[j];

 // We have found a second sheet: compare names
 // we are using case insensitive comparison to avoid mistakes between
 // similar names like Mysheet and mysheet
 if( sheet->GetName().CmpNoCase( test_item->GetName() ) == 0 )
 {
 if( aCreateMarker )
 {
 std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( ERCE_DUPLICATE_SHEET_NAME );
 ercItem->SetItems( sheet, test_item );

 SCH_MARKER* marker = new SCH_MARKER( ercItem, sheet->GetPosition() );
 screen->Append( marker );
 }

 err_count++;
 }
 }
 }
 }

 return err_count;
}


void ERC_TESTER::TestTextVars( DS_PROXY_VIEW_ITEM* aDrawingSheet )
{
 DS_DRAW_ITEM_LIST wsItems;

 auto unresolved = [this]( wxString str )
 {
 str = ExpandEnvVarSubstitutions( str, &m_schematic->Prj() );
 return str.Matches( wxT( "*${*}*" ) );
 };

 if( aDrawingSheet )
 {
 wsItems.SetMilsToIUfactor( IU_PER_MILS );
 wsItems.SetPageNumber( wxT( "1" ) );
 wsItems.SetSheetCount( 1 );
 wsItems.SetFileName( wxT( "dummyFilename" ) );
 wsItems.SetSheetName( wxT( "dummySheet" ) );
 wsItems.SetSheetLayer( wxT( "dummyLayer" ) );
 wsItems.SetProject( &m_schematic->Prj() );
 wsItems.BuildDrawItemsList( aDrawingSheet->GetPageInfo(), aDrawingSheet->GetTitleBlock());
 }

 SCH_SHEET_PATH savedCurrentSheet = m_schematic->CurrentSheet();
 SCH_SHEET_LIST sheets = m_schematic->GetSheets();

 for( SCH_SHEET_PATH& sheet : sheets )
 {
 m_schematic->SetCurrentSheet( sheet );
 SCH_SCREEN* screen = sheet.LastScreen();

 for( SCH_ITEM* item : screen->Items().OfType( SCH_LOCATE_ANY_T ) )
 {
 if( item->Type() == SCH_SYMBOL_T )
 {
 SCH_SYMBOL* symbol = static_cast<SCH_SYMBOL*>( item );

 for( SCH_FIELD& field : symbol->GetFields() )
 {
 if( unresolved( field.GetShownText() ) )
 {
 wxPoint pos = field.GetPosition() - symbol->GetPosition();
 pos = symbol->GetTransform().TransformCoordinate( pos );
 pos += symbol->GetPosition();

 std::shared_ptr<ERC_ITEM> ercItem =
 ERC_ITEM::Create( ERCE_UNRESOLVED_VARIABLE );
 ercItem->SetItems( &field );

 SCH_MARKER* marker = new SCH_MARKER( ercItem, pos );
 screen->Append( marker );
 }
 }
 }
 else if( item->Type() == SCH_SHEET_T )
 {
 SCH_SHEET* subSheet = static_cast<SCH_SHEET*>( item );

 for( SCH_FIELD& field : subSheet->GetFields() )
 {
 if( unresolved( field.GetShownText() ) )
 {
 std::shared_ptr<ERC_ITEM> ercItem =
 ERC_ITEM::Create( ERCE_UNRESOLVED_VARIABLE );
 ercItem->SetItems( &field );

 SCH_MARKER* marker = new SCH_MARKER( ercItem, field.GetPosition() );
 screen->Append( marker );
 }
 }

 for( SCH_SHEET_PIN* pin : static_cast<SCH_SHEET*>( item )->GetPins() )
 {
 if( pin->GetShownText().Matches( wxT( "*${*}*" ) ) )
 {
 std::shared_ptr<ERC_ITEM> ercItem =
 ERC_ITEM::Create( ERCE_UNRESOLVED_VARIABLE );
 ercItem->SetItems( pin );

 SCH_MARKER* marker = new SCH_MARKER( ercItem, pin->GetPosition() );
 screen->Append( marker );
 }
 }
 }
 else if( SCH_TEXT* text = dynamic_cast<SCH_TEXT*>( item ) )
 {
 if( text->GetShownText().Matches( wxT( "*${*}*" ) ) )
 {
 std::shared_ptr<ERC_ITEM> ercItem =
 ERC_ITEM::Create( ERCE_UNRESOLVED_VARIABLE );
 ercItem->SetItems( text );

 SCH_MARKER* marker = new SCH_MARKER( ercItem, text->GetPosition() );
 screen->Append( marker );
 }
 }
 }

 for( DS_DRAW_ITEM_BASE* item = wsItems.GetFirst(); item; item = wsItems.GetNext() )
 {
 if( DS_DRAW_ITEM_TEXT* text = dynamic_cast<DS_DRAW_ITEM_TEXT*>( item ) )
 {
 if( text->GetShownText().Matches( wxT( "*${*}*" ) ) )
 {
 std::shared_ptr<ERC_ITEM> ercItem =
 ERC_ITEM::Create( ERCE_UNRESOLVED_VARIABLE );
 ercItem->SetErrorMessage( _( "Unresolved text variable in drawing sheet." ) );

 SCH_MARKER* marker = new SCH_MARKER( ercItem, text->GetPosition() );
 screen->Append( marker );
 }
 }
 }
 }

 m_schematic->SetCurrentSheet( savedCurrentSheet );
}


int ERC_TESTER::TestConflictingBusAliases()
{
 wxString msg;
 int err_count = 0;

 SCH_SCREENS screens( m_schematic->Root() );
 std::vector< std::shared_ptr<BUS_ALIAS> > aliases;

 for( SCH_SCREEN* screen = screens.GetFirst(); screen != nullptr; screen = screens.GetNext() )
 {
 std::unordered_set< std::shared_ptr<BUS_ALIAS> > screen_aliases = screen->GetBusAliases();

 for( const std::shared_ptr<BUS_ALIAS>& alias : screen_aliases )
 {
 for( const std::shared_ptr<BUS_ALIAS>& test : aliases )
 {
 if( alias->GetName() == test->GetName() && alias->Members() != test->Members() )
 {
 msg.Printf( _( "Bus alias %s has conflicting definitions on %s and %s" ),
 alias->GetName(),
 alias->GetParent()->GetFileName(),
 test->GetParent()->GetFileName() );

 std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( ERCE_BUS_ALIAS_CONFLICT );
 ercItem->SetErrorMessage( msg );

 SCH_MARKER* marker = new SCH_MARKER( ercItem, wxPoint() );
 test->GetParent()->Append( marker );

 ++err_count;
 }
 }
 }

 aliases.insert( aliases.end(), screen_aliases.begin(), screen_aliases.end() );
 }

 return err_count;
}


int ERC_TESTER::TestMultiunitFootprints()
{
 SCH_SHEET_LIST sheets = m_schematic->GetSheets();

 int errors = 0;
 std::map<wxString, LIB_ID> footprints;
 SCH_MULTI_UNIT_REFERENCE_MAP refMap;
 sheets.GetMultiUnitSymbols( refMap, true );

 for( std::pair<const wxString, SCH_REFERENCE_LIST>& symbol : refMap )
 {
 SCH_REFERENCE_LIST& refList = symbol.second;

 if( refList.GetCount() == 0 )
 {
 wxFAIL; // it should not happen
 continue;
 }

 // Reference footprint
 SCH_SYMBOL* unit = nullptr;
 wxString unitName;
 wxString unitFP;

 for( unsigned i = 0; i < refList.GetCount(); ++i )
 {
 SCH_SHEET_PATH sheetPath = refList.GetItem( i ).GetSheetPath();
 unitFP = refList.GetItem( i ).GetFootprint();

 if( !unitFP.IsEmpty() )
 {
 unit = refList.GetItem( i ).GetSymbol();
 unitName = unit->GetRef( &sheetPath, true );
 break;
 }
 }

 for( unsigned i = 0; i < refList.GetCount(); ++i )
 {
 SCH_REFERENCE& secondRef = refList.GetItem( i );
 SCH_SYMBOL* secondUnit = secondRef.GetSymbol();
 wxString secondName = secondUnit->GetRef( &secondRef.GetSheetPath(), true );
 const wxString secondFp = secondRef.GetFootprint();
 wxString msg;

 if( unit && !secondFp.IsEmpty() && unitFP != secondFp )
 {
 msg.Printf( _( "Different footprints assigned to %s and %s" ),
 unitName, secondName );

 std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( ERCE_DIFFERENT_UNIT_FP );
 ercItem->SetErrorMessage( msg );
 ercItem->SetItems( unit, secondUnit );

 SCH_MARKER* marker = new SCH_MARKER( ercItem, secondUnit->GetPosition() );
 secondRef.GetSheetPath().LastScreen()->Append( marker );

 ++errors;
 }
 }
 }

 return errors;
}


int ERC_TESTER::TestNoConnectPins()
{
 int err_count = 0;

 for( const SCH_SHEET_PATH& sheet : m_schematic->GetSheets() )
 {
 std::map<wxPoint, std::vector<SCH_PIN*>> pinMap;

 for( SCH_ITEM* item : sheet.LastScreen()->Items().OfType( SCH_SYMBOL_T ) )
 {
 SCH_SYMBOL* symbol = static_cast<SCH_SYMBOL*>( item );

 for( SCH_PIN* pin : symbol->GetPins( &sheet ) )
 {
 if( pin->GetLibPin()->GetType() == ELECTRICAL_PINTYPE::PT_NC )
 pinMap[pin->GetPosition()].emplace_back( pin );
 }
 }

 for( auto& pair : pinMap )
 {
 if( pair.second.size() > 1 )
 {
 err_count++;

 std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( ERCE_NOCONNECT_CONNECTED );

 ercItem->SetItems( pair.second[0], pair.second[1],
 pair.second.size() > 2 ? pair.second[2] : nullptr,
 pair.second.size() > 3 ? pair.second[3] : nullptr );
 ercItem->SetErrorMessage( _( "Pins with \"no connection\" type are connected" ) );

 SCH_MARKER* marker = new SCH_MARKER( ercItem, pair.first );
 sheet.LastScreen()->Append( marker );
 }
 }
 }

 return err_count;
}


int ERC_TESTER::TestPinToPin()
{
 ERC_SETTINGS& settings = m_schematic->ErcSettings();
 const NET_MAP& nets = m_schematic->ConnectionGraph()->GetNetMap();

 int errors = 0;

 for( const std::pair<NET_NAME_CODE, std::vector<CONNECTION_SUBGRAPH*>> net : nets )
 {
 std::vector<SCH_PIN*> pins;
 std::unordered_map<EDA_ITEM*, SCH_SCREEN*> pinToScreenMap;
 bool has_noconnect = false;

 for( CONNECTION_SUBGRAPH* subgraph: net.second )
 {
 if( subgraph->m_no_connect )
 has_noconnect = true;

 for( EDA_ITEM* item : subgraph->m_items )
 {
 if( item->Type() == SCH_PIN_T )
 {
 pins.emplace_back( static_cast<SCH_PIN*>( item ) );
 pinToScreenMap[item] = subgraph->m_sheet.LastScreen();
 }
 }
 }

 std::set<std::pair<SCH_PIN*, SCH_PIN*>> tested;

 SCH_PIN* needsDriver = nullptr;
 bool hasDriver = false;

 // We need different drivers for power nets and normal nets.
 // A power net has at least one pin having the ELECTRICAL_PINTYPE::PT_POWER_IN
 // and power nets can be driven only by ELECTRICAL_PINTYPE::PT_POWER_OUT pins
 bool ispowerNet = false;

 for( SCH_PIN* refPin : pins )
 {
 if( refPin->GetType() == ELECTRICAL_PINTYPE::PT_POWER_IN )
 {
 ispowerNet = true;
 break;
 }
 }

 for( SCH_PIN* refPin : pins )
 {
 ELECTRICAL_PINTYPE refType = refPin->GetType();

 if( DrivenPinTypes.count( refType ) )
 {
 // needsDriver will be the pin shown in the error report eventually, so try to
 // upgrade to a "better" pin if possible: something visible and only a power symbol
 // if this net needs a power driver
 if( !needsDriver ||
 ( !needsDriver->IsVisible() && refPin->IsVisible() ) ||
 ( ispowerNet != ( needsDriver->GetType() == ELECTRICAL_PINTYPE::PT_POWER_IN ) &&
 ispowerNet == ( refType == ELECTRICAL_PINTYPE::PT_POWER_IN ) ) )
 {
 needsDriver = refPin;
 }
 }

 if( ispowerNet )
 hasDriver |= ( DrivingPowerPinTypes.count( refType ) != 0 );
 else
 hasDriver |= ( DrivingPinTypes.count( refType ) != 0 );

 for( SCH_PIN* testPin : pins )
 {
 if( testPin == refPin )
 continue;

 std::pair<SCH_PIN*, SCH_PIN*> pair1 = std::make_pair( refPin, testPin );
 std::pair<SCH_PIN*, SCH_PIN*> pair2 = std::make_pair( testPin, refPin );

 if( tested.count( pair1 ) || tested.count( pair2 ) )
 continue;

 tested.insert( pair1 );
 tested.insert( pair2 );

 ELECTRICAL_PINTYPE testType = testPin->GetType();

 if( ispowerNet )
 hasDriver |= ( DrivingPowerPinTypes.count( testType ) != 0 );
 else
 hasDriver |= ( DrivingPinTypes.count( testType ) != 0 );

 PIN_ERROR erc = settings.GetPinMapValue( refType, testType );

 if( erc != PIN_ERROR::OK && settings.IsTestEnabled( ERCE_PIN_TO_PIN_WARNING ) )
 {
 std::shared_ptr<ERC_ITEM> ercItem =
 ERC_ITEM::Create( erc == PIN_ERROR::WARNING ? ERCE_PIN_TO_PIN_WARNING :
 ERCE_PIN_TO_PIN_ERROR );
 ercItem->SetItems( refPin, testPin );
 ercItem->SetIsSheetSpecific();

 ercItem->SetErrorMessage(
 wxString::Format( _( "Pins of type %s and %s are connected" ),
 ElectricalPinTypeGetText( refType ),
 ElectricalPinTypeGetText( testType ) ) );

 SCH_MARKER* marker = new SCH_MARKER( ercItem,
 refPin->GetTransformedPosition() );
 pinToScreenMap[refPin]->Append( marker );
 errors++;
 }
 }
 }

 if( needsDriver && !hasDriver && !has_noconnect )
 {
 int err_code = ispowerNet ? ERCE_POWERPIN_NOT_DRIVEN : ERCE_PIN_NOT_DRIVEN;

 if( settings.IsTestEnabled( err_code ) )
 {
 std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( err_code );

 ercItem->SetItems( needsDriver );

 SCH_MARKER* marker = new SCH_MARKER( ercItem,
 needsDriver->GetTransformedPosition() );
 pinToScreenMap[needsDriver]->Append( marker );
 errors++;
 }
 }
 }

 return errors;
}


int ERC_TESTER::TestMultUnitPinConflicts()
{
 const NET_MAP& nets = m_schematic->ConnectionGraph()->GetNetMap();

 int errors = 0;

 std::unordered_map<wxString, std::pair<wxString, SCH_PIN*>> pinToNetMap;

 for( const std::pair<NET_NAME_CODE, std::vector<CONNECTION_SUBGRAPH*>> net : nets )
 {
 const wxString& netName = net.first.first;
 std::vector<SCH_PIN*> pins;

 for( CONNECTION_SUBGRAPH* subgraph : net.second )
 {
 for( EDA_ITEM* item : subgraph->m_items )
 {
 if( item->Type() == SCH_PIN_T )
 {
 SCH_PIN* pin = static_cast<SCH_PIN*>( item );

 if( !pin->GetLibPin()->GetParent()->IsMulti() )
 continue;

 wxString name = pin->GetParentSymbol()->GetRef( &subgraph->m_sheet ) +
 + wxT( ":" ) + pin->GetShownNumber();

 if( !pinToNetMap.count( name ) )
 {
 pinToNetMap[name] = std::make_pair( netName, pin );
 }
 else if( pinToNetMap[name].first != netName )
 {
 std::shared_ptr<ERC_ITEM> ercItem =
 ERC_ITEM::Create( ERCE_DIFFERENT_UNIT_NET );

 ercItem->SetErrorMessage( wxString::Format(
 _( "Pin %s is connected to both %s and %s" ),
 pin->GetShownNumber(),
 netName,
 pinToNetMap[name].first ) );

 ercItem->SetItems( pin, pinToNetMap[name].second );
 ercItem->SetIsSheetSpecific();

 SCH_MARKER* marker = new SCH_MARKER( ercItem,
 pin->GetTransformedPosition() );
 subgraph->m_sheet.LastScreen()->Append( marker );
 errors += 1;
 }
 }
 }
 }
 }

 return errors;
}


int ERC_TESTER::TestSimilarLabels()
{
 const NET_MAP& nets = m_schematic->ConnectionGraph()->GetNetMap();

 int errors = 0;

 std::unordered_map<wxString, SCH_TEXT*> labelMap;

 for( const std::pair<NET_NAME_CODE, std::vector<CONNECTION_SUBGRAPH*>> net : nets )
 {
 std::vector<SCH_PIN*> pins;

 for( CONNECTION_SUBGRAPH* subgraph : net.second )
 {
 for( EDA_ITEM* item : subgraph->m_items )
 {
 switch( item->Type() )
 {
 case SCH_LABEL_T:
 case SCH_HIER_LABEL_T:
 case SCH_GLOBAL_LABEL_T:
 {
 SCH_TEXT* text = static_cast<SCH_TEXT*>( item );

 wxString normalized = text->GetShownText().Lower();

 if( !labelMap.count( normalized ) )
 {
 labelMap[normalized] = text;
 }
 else if( labelMap.at( normalized )->GetShownText() != text->GetShownText() )
 {
 std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( ERCE_SIMILAR_LABELS );
 ercItem->SetItems( text, labelMap.at( normalized ) );

 SCH_MARKER* marker = new SCH_MARKER( ercItem, text->GetPosition() );
 subgraph->m_sheet.LastScreen()->Append( marker );
 errors += 1;
 }

 break;
 }

 default:
 break;
 }
 }
 }
 }

 return errors;
}


int ERC_TESTER::TestLibSymbolIssues()
{
 wxCHECK( m_schematic, 0 );

 SYMBOL_LIB_TABLE* libTable = m_schematic->Prj().SchSymbolLibTable();
 wxString msg;
 int err_count = 0;

 SCH_SCREENS screens( m_schematic->Root() );

 for( SCH_SCREEN* screen = screens.GetFirst(); screen != nullptr; screen = screens.GetNext() )
 {
 std::vector<SCH_MARKER*> markers;

 for( SCH_ITEM* item : screen->Items().OfType( SCH_SYMBOL_T ) )
 {
 SCH_SYMBOL* symbol = dynamic_cast<SCH_SYMBOL*>( item );

 wxCHECK2( symbol, continue );

 LIB_SYMBOL* libSymbolInSchematic = symbol->GetLibSymbolRef().get();

 wxCHECK2( libSymbolInSchematic, continue );

 wxString libName = symbol->GetLibId().GetLibNickname();
 LIB_TABLE_ROW* libTableRow = libTable->FindRow( libName, true );

 if( !libTableRow )
 {
 std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( ERCE_LIB_SYMBOL_ISSUES );
 ercItem->SetItems( symbol );
 msg.Printf( _( "The current configuration does not include the library '%s'." ),
 UnescapeString( libName ) );
 ercItem->SetErrorMessage( msg );

 markers.emplace_back( new SCH_MARKER( ercItem, symbol->GetPosition() ) );
 continue;
 }
 else if( !libTable->HasLibrary( libName, true ) )
 {
 std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( ERCE_LIB_SYMBOL_ISSUES );
 ercItem->SetItems( symbol );
 msg.Printf( _( "The library '%s' is not enabled in the current configuration." ),
 UnescapeString( libName ) );
 ercItem->SetErrorMessage( msg );

 markers.emplace_back( new SCH_MARKER( ercItem, symbol->GetPosition() ) );
 continue;
 }

 wxString symbolName = symbol->GetLibId().GetLibItemName();
 LIB_SYMBOL* libSymbol = SchGetLibSymbol( symbol->GetLibId(), libTable );

 if( libSymbol == nullptr )
 {
 std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( ERCE_LIB_SYMBOL_ISSUES );
 ercItem->SetItems( symbol );
 msg.Printf( wxT( "Symbol '%s' not found in symbol library '%s'." ),
 UnescapeString( symbolName ),
 UnescapeString( libName ) );
 ercItem->SetErrorMessage( msg );

 markers.emplace_back( new SCH_MARKER( ercItem, symbol->GetPosition() ) );
 continue;
 }

 std::unique_ptr<LIB_SYMBOL> flattenedSymbol = libSymbol->Flatten();
 constexpr int flags = LIB_ITEM::COMPARE_FLAGS::EQUALITY | LIB_ITEM::COMPARE_FLAGS::ERC;

 if( flattenedSymbol->Compare( *libSymbolInSchematic, flags ) != 0 )
 {
 std::shared_ptr<ERC_ITEM> ercItem = ERC_ITEM::Create( ERCE_LIB_SYMBOL_ISSUES );
 ercItem->SetItems( symbol );
 msg.Printf( wxT( "Symbol '%s' has been modified in library '%s'." ),
 UnescapeString( symbolName ),
 UnescapeString( libName ) );
 ercItem->SetErrorMessage( msg );

 markers.emplace_back( new SCH_MARKER( ercItem, symbol->GetPosition() ) );
 }
 }

 for( SCH_MARKER* marker : markers )
 {
 screen->Append( marker );
 err_count += 1;
 }
 }

 return err_count;
}