Move pad checking to Footprint Checker.

Fixes https://gitlab.com/kicad/code/kicad/-/issues/18102

pcbnew/dialogs/dialog_footprint_checker.cpp

@@ -151,7 +151,7 @@ void DIALOG_FOOTPRINT_CHECKER::runChecks()
                               { 0, 0 } );
             } );
 
-    footprint->CheckPads(
+    footprint->CheckPads( m_frame,
             [&]( const PAD* aPad, int aErrorCode, const wxString& aMsg )
             {
                 errorHandler( aPad, nullptr, nullptr, aErrorCode, aMsg, aPad->GetPosition() );

pcbnew/dialogs/dialog_pad_properties.cpp

@@ -24,6 +24,7 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
  */
 
+#include <drc/drc_item.h>
 #include <base_units.h>
 #include <bitmaps.h>
 #include <board_commit.h>
@@ -1258,216 +1259,21 @@ void DIALOG_PAD_PROPERTIES::OnSetLayers( wxCommandEvent& event )
 
 bool DIALOG_PAD_PROPERTIES::padValuesOK()
 {
-    bool error = !transferDataToPad( m_previewPad );
+    transferDataToPad( m_previewPad );
 
     wxArrayString error_msgs;
     wxArrayString warning_msgs;
-    VECTOR2I      pad_size = m_previewPad->GetSize();
-    VECTOR2I      drill_size = m_previewPad->GetDrillSize();
 
-    if( m_previewPad->GetShape() == PAD_SHAPE::CUSTOM )
+    m_previewPad->CheckPad( m_parentFrame,
-    {
+            [&]( int errorCode, const wxString& msg )
-        pad_size = m_previewPad->GetBoundingBox().GetSize();
-    }
-    else if( m_previewPad->GetShape() == PAD_SHAPE::CIRCLE )
-    {
-        if( pad_size.x <= 0 )
-            error_msgs.Add( _( "Error: Pad must have a positive size." ) );
-    }
-    else
-    {
-        if( pad_size.x <= 0 || pad_size.y <= 0 )
-            error_msgs.Add( _( "Error: Pad must have a positive size." ) );
-    }
-
-    // Test hole against pad shape
-    if( m_previewPad->IsOnCopperLayer() && m_previewPad->GetDrillSize().x > 0 )
-    {
-        int            maxError = m_board->GetDesignSettings().m_MaxError;
-        SHAPE_POLY_SET padOutline;
-
-        m_previewPad->TransformShapeToPolygon( padOutline, UNDEFINED_LAYER, 0, maxError,
-                                             ERROR_INSIDE );
-
-        if( !padOutline.Collide( m_previewPad->GetPosition() ) )
-        {
-            warning_msgs.Add( _( "Warning: Pad hole not inside pad shape." ) );
-        }
-        else if( m_previewPad->GetAttribute() == PAD_ATTRIB::PTH )
-        {
-            std::shared_ptr<SHAPE_SEGMENT> slot = m_previewPad->GetEffectiveHoleShape();
-            SHAPE_POLY_SET                 slotOutline;
-
-            TransformOvalToPolygon( slotOutline, slot->GetSeg().A, slot->GetSeg().B,
-                                    slot->GetWidth(), maxError, ERROR_INSIDE );
-
-            padOutline.BooleanSubtract( slotOutline, SHAPE_POLY_SET::PM_FAST );
-
-            if( padOutline.IsEmpty() )
-                warning_msgs.Add( _( "Warning: Pad hole will leave no copper." ) );
-        }
-    }
-
-    if( m_previewPad->GetLocalClearance().value_or( 0 ) < 0 )
-        warning_msgs.Add( _( "Warning: Negative local clearance values will have no effect." ) );
-
-    // Some pads need a negative solder mask clearance (mainly for BGA with small pads)
-    // However the negative solder mask clearance must not create negative mask size
-    // Therefore test for minimal acceptable negative value
-    std::optional<int> solderMaskMargin = m_previewPad->GetLocalSolderMaskMargin();
-
-    if( solderMaskMargin.has_value() && solderMaskMargin.value() < 0 )
-    {
-        int absMargin = abs( solderMaskMargin.value() );
-
-        if( m_previewPad->GetShape() == PAD_SHAPE::CUSTOM )
-        {
-            for( const std::shared_ptr<PCB_SHAPE>& shape : m_previewPad->GetPrimitives() )
             {
-                BOX2I shapeBBox = shape->GetBoundingBox();
+                if( errorCode == DRCE_PADSTACK_INVALID )
-
+                    error_msgs.Add( _( "Error: " ) + msg );
-                if( absMargin > shapeBBox.GetWidth() || absMargin > shapeBBox.GetHeight() )
+                else if( errorCode == DRCE_PADSTACK )
-                {
+                    warning_msgs.Add( _( "Warning: " ) + msg );
-                    warning_msgs.Add( _( "Warning: Negative solder mask clearances larger than "
+                else if( errorCode == DRCE_PAD_TH_WITH_NO_HOLE )
-                                         "some shape primitives. Results may be surprising." ) );
+                    error_msgs.Add( _( "Error: Through hole pad has no hole." ) );
-
+            } );
-                    break;
-                }
-            }
-        }
-        else if( absMargin > pad_size.x || absMargin > pad_size.y )
-        {
-            warning_msgs.Add( _( "Warning: Negative solder mask clearance larger than pad. No "
-                                 "solder mask will be generated." ) );
-        }
-    }
-
-    // Some pads need a positive solder paste clearance (mainly for BGA with small pads)
-    // However, a positive value can create issues if the resulting shape is too big.
-    // (like a solder paste creating a solder paste area on a neighbor pad or on the solder mask)
-    // So we could ask for user to confirm the choice
-    // For now we just check for disappearing paste
-    wxSize paste_size;
-    int    paste_margin = m_previewPad->GetLocalSolderPasteMargin().value_or( 0 );
-    double paste_ratio = m_previewPad->GetLocalSolderPasteMarginRatio().value_or( 0 );
-
-    paste_size.x = pad_size.x + paste_margin + KiROUND( pad_size.x * paste_ratio );
-    paste_size.y = pad_size.y + paste_margin + KiROUND( pad_size.y * paste_ratio );
-
-    if( paste_size.x <= 0 || paste_size.y <= 0 )
-    {
-        warning_msgs.Add( _( "Warning: Negative solder paste margins larger than pad. No solder "
-                             "paste mask will be generated." ) );
-    }
-
-    LSET padlayers_mask = m_previewPad->GetLayerSet();
-
-    if( padlayers_mask == 0 )
-        error_msgs.Add( _( "Error: pad has no layer." ) );
-
-    if( !padlayers_mask[F_Cu] && !padlayers_mask[B_Cu] )
-    {
-        if( ( drill_size.x || drill_size.y ) && m_previewPad->GetAttribute() != PAD_ATTRIB::NPTH )
-        {
-            warning_msgs.Add( _( "Warning: Plated through holes should normally have a copper pad "
-                                 "on at least one layer." ) );
-        }
-    }
-
-    if( error )
-        error_msgs.Add(  _( "Error: Trapazoid delta is too large." ) );
-
-    switch( m_previewPad->GetAttribute() )
-    {
-    case PAD_ATTRIB::NPTH:   // Not plated, but through hole, a hole is expected
-    case PAD_ATTRIB::PTH:    // Pad through hole, a hole is also expected
-        if( drill_size.x <= 0
-            || ( drill_size.y <= 0 && m_previewPad->GetDrillShape() == PAD_DRILL_SHAPE::OBLONG ) )
-        {
-            error_msgs.Add( _( "Error: Through hole pad has no hole." ) );
-        }
-        break;
-
-    case PAD_ATTRIB::CONN:      // Connector pads are smd pads, just they do not have solder paste.
-        if( padlayers_mask[B_Paste] || padlayers_mask[F_Paste] )
-        {
-            warning_msgs.Add( _( "Warning: Connector pads normally have no solder paste. Use a "
-                                 "SMD pad instead." ) );
-        }
-        KI_FALLTHROUGH;
-
-    case PAD_ATTRIB::SMD:       // SMD and Connector pads (One external copper layer only)
-    {
-        if( drill_size.x > 0 || drill_size.y > 0 )
-        {
-            error_msgs.Add( _( "Error: SMD pad has a hole." ) );
-        }
-
-        LSET innerlayers_mask = padlayers_mask & LSET::InternalCuMask();
-
-        if( ( padlayers_mask[F_Cu] && padlayers_mask[B_Cu] ) || innerlayers_mask.count() != 0 )
-            warning_msgs.Add( _( "Warning: SMD pad has no outer layers." ) );
-    }
-        break;
-    }
-
-    if( ( m_previewPad->GetProperty() == PAD_PROP::FIDUCIAL_GLBL || m_previewPad->GetProperty() == PAD_PROP::FIDUCIAL_LOCAL )
-            && m_previewPad->GetAttribute() == PAD_ATTRIB::NPTH )
-    {
-        warning_msgs.Add(  _( "Warning: Fiducial property makes no sense on NPTH pads." ) );
-    }
-
-    if( m_previewPad->GetProperty() == PAD_PROP::TESTPOINT
-            && m_previewPad->GetAttribute() == PAD_ATTRIB::NPTH )
-    {
-        warning_msgs.Add(  _( "Warning: Testpoint property makes no sense on NPTH pads." ) );
-    }
-
-    if( m_previewPad->GetProperty() == PAD_PROP::HEATSINK
-            && m_previewPad->GetAttribute() == PAD_ATTRIB::NPTH )
-    {
-        warning_msgs.Add(  _( "Warning: Heatsink property makes no sense of NPTH pads." ) );
-    }
-
-    if( m_previewPad->GetProperty() == PAD_PROP::CASTELLATED
-            && m_previewPad->GetAttribute() != PAD_ATTRIB::PTH )
-    {
-        warning_msgs.Add(  _( "Warning: Castellated property is for PTH pads." ) );
-    }
-
-    if( m_previewPad->GetProperty() == PAD_PROP::BGA
-            && m_previewPad->GetAttribute() != PAD_ATTRIB::SMD )
-    {
-        warning_msgs.Add(  _( "Warning: BGA property is for SMD pads." ) );
-    }
-
-    if( m_previewPad->GetProperty() == PAD_PROP::MECHANICAL
-            && m_previewPad->GetAttribute() != PAD_ATTRIB::PTH )
-    {
-        warning_msgs.Add(  _( "Warning: Mechanical property is for PTH pads." ) );
-    }
-
-    if( m_previewPad->GetShape() == PAD_SHAPE::ROUNDRECT
-            || m_previewPad->GetShape() == PAD_SHAPE::CHAMFERED_RECT )
-    {
-        wxASSERT( m_cornerRatio.GetDoubleValue() == m_mixedCornerRatio.GetDoubleValue() );
-
-        if( m_cornerRatio.GetDoubleValue() < 0.0 )
-            error_msgs.Add( _( "Error: Negative corner size." ) );
-        else if( m_cornerRatio.GetDoubleValue() > 50.0 )
-            warning_msgs.Add( _( "Warning: Corner size will make pad circular." ) );
-    }
-
-    // PADSTACKS TODO: this will need to check each layer in the pad...
-    if( m_previewPad->GetShape() == PAD_SHAPE::CUSTOM )
-    {
-        SHAPE_POLY_SET mergedPolygon;
-        m_previewPad->MergePrimitivesAsPolygon( &mergedPolygon );
-
-        if( mergedPolygon.OutlineCount() > 1 )
-            error_msgs.Add( _( "Error: Custom pad shape must resolve to a single polygon." ) );
-    }
-
 
     if( error_msgs.GetCount() || warning_msgs.GetCount() )
     {

pcbnew/drc/drc_item.cpp

@@ -130,9 +130,13 @@ DRC_ITEM DRC_ITEM::viaDiameter( DRCE_VIA_DIAMETER,
         wxT( "via_diameter" ) );
 
 DRC_ITEM DRC_ITEM::padstack( DRCE_PADSTACK,
-        _( "Padstack is not valid" ),
+        _( "" ),
         wxT( "padstack" ) );
 
+DRC_ITEM DRC_ITEM::padstackInvalid( DRCE_PADSTACK_INVALID,
+        _( "Padstack is not valid" ),
+        wxT( "padstack_invalid" ) );
+
 DRC_ITEM DRC_ITEM::microviaDrillTooSmall( DRCE_MICROVIA_DRILL_OUT_OF_RANGE,
         _( "Micro via hole size out of range" ),
         wxT( "microvia_drill_out_of_range" ) );
@@ -317,6 +321,8 @@ std::vector<std::reference_wrapper<RC_ITEM>> DRC_ITEM::allItemTypes( {
             DRC_ITEM::isolatedCopper,
             DRC_ITEM::footprint,
             DRC_ITEM::padstack,
+            // Do not include padstackInvalid; it flags invalid states so must always be an error
+            // DRC_ITEM::padStackInvalid;
             DRC_ITEM::pthInsideCourtyard,
             DRC_ITEM::npthInsideCourtyard,
             DRC_ITEM::itemOnDisabledLayer,
@@ -354,6 +360,7 @@ std::shared_ptr<DRC_ITEM> DRC_ITEM::Create( int aErrorCode )
     case DRCE_DRILL_OUT_OF_RANGE:       return std::make_shared<DRC_ITEM>( drillTooSmall );
     case DRCE_VIA_DIAMETER:             return std::make_shared<DRC_ITEM>( viaDiameter );
     case DRCE_PADSTACK:                 return std::make_shared<DRC_ITEM>( padstack );
+    case DRCE_PADSTACK_INVALID:         return std::make_shared<DRC_ITEM>( padstackInvalid );
     case DRCE_MICROVIA_DRILL_OUT_OF_RANGE: return std::make_shared<DRC_ITEM>( microviaDrillTooSmall );
     case DRCE_OVERLAPPING_FOOTPRINTS:   return std::make_shared<DRC_ITEM>( courtyardsOverlap );
     case DRCE_MISSING_COURTYARD:        return std::make_shared<DRC_ITEM>( missingCourtyard );

pcbnew/drc/drc_item.h

@@ -57,6 +57,7 @@ enum PCB_DRC_CODE {
     DRCE_DRILL_OUT_OF_RANGE,             // Too small via or pad drill
     DRCE_VIA_DIAMETER,                   // Via diameter checks (min/max)
     DRCE_PADSTACK,                       // something is wrong with a pad or via stackup
+    DRCE_PADSTACK_INVALID,               // something is invalid with a pad or via stackup
     DRCE_MICROVIA_DRILL_OUT_OF_RANGE,    // Too small micro via drill
     DRCE_OVERLAPPING_FOOTPRINTS,         // footprint courtyards overlap
     DRCE_MISSING_COURTYARD,              // footprint has no courtyard defined
@@ -176,6 +177,7 @@ private:
     static DRC_ITEM drillTooSmall;
     static DRC_ITEM viaDiameter;
     static DRC_ITEM padstack;
+    static DRC_ITEM padstackInvalid;
     static DRC_ITEM microviaDrillTooSmall;
     static DRC_ITEM courtyardsOverlap;
     static DRC_ITEM missingCourtyard;

pcbnew/drc/drc_test_provider_footprint_checks.cpp

@@ -34,6 +34,7 @@
     - DRCE_OVERLAPPING_PADS,
     - DRCE_PAD_TH_WITH_NO_HOLE,
     - DRCE_PADSTACK,
+    - DRCE_PADSTACK_INVALID,
     - DRCE_FOOTPRINT (unknown or duplicate pads in net-tie pad groups),
     - DRCE_SHORTING_ITEMS
 */
@@ -97,7 +98,7 @@ bool DRC_TEST_PROVIDER_FOOTPRINT_CHECKS::Run()
         if( !m_drcEngine->IsErrorLimitExceeded( DRCE_PAD_TH_WITH_NO_HOLE )
                 || !m_drcEngine->IsErrorLimitExceeded( DRCE_PADSTACK ) )
         {
-            footprint->CheckPads(
+            footprint->CheckPads( m_drcEngine,
                     [&]( const PAD* aPad, int aErrorCode, const wxString& aMsg )
                     {
                         if( !m_drcEngine->IsErrorLimitExceeded( aErrorCode ) )

pcbnew/footprint.cpp

@@ -3030,7 +3030,8 @@ void FOOTPRINT::CheckFootprintAttributes( const std::function<void( const wxStri
 }
 
 
-void FOOTPRINT::CheckPads( const std::function<void( const PAD*, int,
+void FOOTPRINT::CheckPads( UNITS_PROVIDER* aUnitsProvider,
+                           const std::function<void( const PAD*, int,
                                                      const wxString& )>& aErrorHandler )
 {
     if( aErrorHandler == nullptr )
@@ -3038,6 +3039,11 @@ void FOOTPRINT::CheckPads( const std::function<void( const PAD*, int,
 
     for( PAD* pad: Pads() )
     {
+        pad->CheckPad( aUnitsProvider,
+                [&]( int errorCode, const wxString& msg )
+                {
+                    aErrorHandler( pad, errorCode, msg );
+                } );
         if( pad->GetAttribute() == PAD_ATTRIB::PTH ||  pad->GetAttribute() == PAD_ATTRIB::NPTH )
         {
             // Ensure the drill size can be handled in next calculations.

pcbnew/footprint.h

@@ -454,7 +454,8 @@ public:
      *
      * @param aErrorHandler callback to handle the error messages generated
      */
-    void CheckPads( const std::function<void( const PAD*, int, const wxString& )>& aErrorHandler );
+    void CheckPads( UNITS_PROVIDER* aUnitsProvider,
+                    const std::function<void( const PAD*, int, const wxString& )>& aErrorHandler );
 
     /**
      * Check for overlapping, different-numbered, non-net-tie pads.

pcbnew/pad.cpp

@@ -58,6 +58,7 @@
 #include <memory>
 #include <macros.h>
 #include <magic_enum.hpp>
+#include <drc/drc_item.h>
 #include "kiface_base.h"
 #include "pcbnew_settings.h"
 
@@ -1901,6 +1902,250 @@ void PAD::TransformShapeToPolygon( SHAPE_POLY_SET& aBuffer, PCB_LAYER_ID aLayer,
 }
 
 
+void PAD::CheckPad( UNITS_PROVIDER* aUnitsProvider,
+                    const std::function<void( int aErrorCode,
+                                              const wxString& aMsg )>& aErrorHandler ) const
+{
+    VECTOR2I pad_size = GetSize();
+    VECTOR2I drill_size = GetDrillSize();
+    wxString msg;
+
+    if( GetShape() == PAD_SHAPE::CUSTOM )
+        pad_size = GetBoundingBox().GetSize();
+    else if( pad_size.x <= 0 || ( pad_size.y <= 0 && GetShape() != PAD_SHAPE::CIRCLE ) )
+        aErrorHandler( DRCE_PADSTACK_INVALID, _( "(Pad must have a positive size)" ) );
+
+    // Test hole against pad shape
+    if( IsOnCopperLayer() && GetDrillSize().x > 0 )
+    {
+        // Ensure the drill size can be handled in next calculations.
+        // Use min size = 4 IU to be able to build a polygon from a hole shape
+        const int min_drill_size = 4;
+
+        if( GetDrillSizeX() <= min_drill_size || GetDrillSizeY() <= min_drill_size )
+        {
+            msg.Printf( _( "(PTH pad hole size must be larger than %s)" ),
+                        aUnitsProvider->StringFromValue( min_drill_size, true ) );
+            aErrorHandler( DRCE_PADSTACK_INVALID, msg );
+        }
+
+        int            maxError = GetBoard()->GetDesignSettings().m_MaxError;
+        SHAPE_POLY_SET padOutline;
+
+        TransformShapeToPolygon( padOutline, UNDEFINED_LAYER, 0, maxError, ERROR_INSIDE );
+
+        if( !padOutline.Collide( GetPosition() ) )
+        {
+            aErrorHandler( DRCE_PADSTACK, _( "Pad hole not inside pad shape" ) );
+        }
+        else if( GetAttribute() == PAD_ATTRIB::PTH )
+        {
+            std::shared_ptr<SHAPE_SEGMENT> slot = GetEffectiveHoleShape();
+            SHAPE_POLY_SET                 slotOutline;
+
+            TransformOvalToPolygon( slotOutline, slot->GetSeg().A, slot->GetSeg().B,
+                                    slot->GetWidth(), maxError, ERROR_OUTSIDE );
+
+            padOutline.BooleanSubtract( slotOutline, SHAPE_POLY_SET::PM_FAST );
+
+            if( padOutline.IsEmpty() )
+                aErrorHandler( DRCE_PADSTACK, _( "Pad hole will leave no copper" ) );
+        }
+    }
+
+    if( GetLocalClearance().value_or( 0 ) < 0 )
+        aErrorHandler( DRCE_PADSTACK, _( "Negative local clearance values have no effect" ) );
+
+    // Some pads need a negative solder mask clearance (mainly for BGA with small pads)
+    // However the negative solder mask clearance must not create negative mask size
+    // Therefore test for minimal acceptable negative value
+    std::optional<int> solderMaskMargin = GetLocalSolderMaskMargin();
+
+    if( solderMaskMargin.has_value() && solderMaskMargin.value() < 0 )
+    {
+        int absMargin = abs( solderMaskMargin.value() );
+
+        if( GetShape() == PAD_SHAPE::CUSTOM )
+        {
+            for( const std::shared_ptr<PCB_SHAPE>& shape : GetPrimitives() )
+            {
+                BOX2I shapeBBox = shape->GetBoundingBox();
+
+                if( absMargin > shapeBBox.GetWidth() || absMargin > shapeBBox.GetHeight() )
+                {
+                    aErrorHandler( DRCE_PADSTACK, _( "Negative solder mask clearance is larger "
+                                                     "than some shape primitives; results may be "
+                                                     "surprising" ) );
+
+                    break;
+                }
+            }
+        }
+        else if( absMargin > pad_size.x || absMargin > pad_size.y )
+        {
+            aErrorHandler( DRCE_PADSTACK, _( "Negative solder mask clearance is larger than pad; "
+                                             "no solder mask will be generated" ) );
+        }
+    }
+
+    // Some pads need a positive solder paste clearance (mainly for BGA with small pads)
+    // However, a positive value can create issues if the resulting shape is too big.
+    // (like a solder paste creating a solder paste area on a neighbor pad or on the solder mask)
+    // So we could ask for user to confirm the choice
+    // For now we just check for disappearing paste
+    wxSize paste_size;
+    int    paste_margin = GetLocalSolderPasteMargin().value_or( 0 );
+    double paste_ratio = GetLocalSolderPasteMarginRatio().value_or( 0 );
+
+    paste_size.x = pad_size.x + paste_margin + KiROUND( pad_size.x * paste_ratio );
+    paste_size.y = pad_size.y + paste_margin + KiROUND( pad_size.y * paste_ratio );
+
+    if( paste_size.x <= 0 || paste_size.y <= 0 )
+    {
+        aErrorHandler( DRCE_PADSTACK, _( "Negative solder paste margin is larger than pad; "
+                                         "no solder paste mask will be generated" ) );
+    }
+
+    LSET padlayers_mask = GetLayerSet();
+
+    if( padlayers_mask == 0 )
+        aErrorHandler( DRCE_PADSTACK_INVALID, _( "(Pad has no layer)" ) );
+
+    if( GetAttribute() == PAD_ATTRIB::PTH && !IsOnCopperLayer() )
+        aErrorHandler( DRCE_PADSTACK, _( "PTH pad has no copper layers" ) );
+
+    if( !padlayers_mask[F_Cu] && !padlayers_mask[B_Cu] )
+    {
+        if( ( drill_size.x || drill_size.y ) && GetAttribute() != PAD_ATTRIB::NPTH )
+        {
+            aErrorHandler( DRCE_PADSTACK, _( "Plated through holes normally have a copper pad on "
+                                             "at least one layer" ) );
+        }
+    }
+
+    switch( GetAttribute() )
+    {
+    case PAD_ATTRIB::NPTH:   // Not plated, but through hole, a hole is expected
+    case PAD_ATTRIB::PTH:    // Pad through hole, a hole is also expected
+        if( drill_size.x <= 0
+            || ( drill_size.y <= 0 && GetDrillShape() == PAD_DRILL_SHAPE::OBLONG ) )
+        {
+            aErrorHandler( DRCE_PAD_TH_WITH_NO_HOLE, wxEmptyString );
+        }
+        break;
+
+    case PAD_ATTRIB::CONN:      // Connector pads are smd pads, just they do not have solder paste.
+        if( padlayers_mask[B_Paste] || padlayers_mask[F_Paste] )
+        {
+            aErrorHandler( DRCE_PADSTACK, _( "Connector pads normally have no solder paste; use a "
+                                             "SMD pad instead" ) );
+        }
+        KI_FALLTHROUGH;
+
+    case PAD_ATTRIB::SMD:       // SMD and Connector pads (One external copper layer only)
+    {
+        if( drill_size.x > 0 || drill_size.y > 0 )
+            aErrorHandler( DRCE_PADSTACK_INVALID, _( "(SMD pad has a hole)" ) );
+
+        LSET innerlayers_mask = padlayers_mask & LSET::InternalCuMask();
+
+        if( IsOnLayer( F_Cu ) && IsOnLayer( B_Cu ) )
+        {
+            aErrorHandler( DRCE_PADSTACK, _( "SMD pad has copper on both sides of the board" ) );
+        }
+        else if( IsOnLayer( F_Cu ) )
+        {
+            if( IsOnLayer( B_Mask ) )
+            {
+                aErrorHandler( DRCE_PADSTACK, _( "SMD pad has copper and mask layers on different "
+                                                 "sides of the board" ) );
+            }
+            else if( IsOnLayer( B_Paste ) )
+            {
+                aErrorHandler( DRCE_PADSTACK, _( "SMD pad has copper and paste layers on different "
+                                                 "sides of the board" ) );
+            }
+        }
+        else if( IsOnLayer( B_Cu ) )
+        {
+            if( IsOnLayer( F_Mask ) )
+            {
+                aErrorHandler( DRCE_PADSTACK, _( "SMD pad has copper and mask layers on different "
+                                                 "sides of the board" ) );
+            }
+            else if( IsOnLayer( F_Paste ) )
+            {
+                aErrorHandler( DRCE_PADSTACK, _( "SMD pad has copper and paste layers on different "
+                                                 "sides of the board" ) );
+            }
+        }
+        else if( innerlayers_mask.count() != 0 )
+        {
+            aErrorHandler( DRCE_PADSTACK, _( "SMD pad has no outer layers" ) );
+        }
+
+        break;
+    }
+    }
+
+    if( ( GetProperty() == PAD_PROP::FIDUCIAL_GLBL || GetProperty() == PAD_PROP::FIDUCIAL_LOCAL )
+            && GetAttribute() == PAD_ATTRIB::NPTH )
+    {
+        aErrorHandler( DRCE_PADSTACK, _( "Fiducial property makes no sense on NPTH pads" ) );
+    }
+
+    if( GetProperty() == PAD_PROP::TESTPOINT && GetAttribute() == PAD_ATTRIB::NPTH )
+        aErrorHandler( DRCE_PADSTACK, _( "Testpoint property makes no sense on NPTH pads" ) );
+
+    if( GetProperty() == PAD_PROP::HEATSINK && GetAttribute() == PAD_ATTRIB::NPTH )
+        aErrorHandler( DRCE_PADSTACK, _( "Heatsink property makes no sense of NPTH pads" ) );
+
+    if( GetProperty() == PAD_PROP::CASTELLATED && GetAttribute() != PAD_ATTRIB::PTH )
+        aErrorHandler( DRCE_PADSTACK, _( "Castellated property is for PTH pads" ) );
+
+    if( GetProperty() == PAD_PROP::BGA && GetAttribute() != PAD_ATTRIB::SMD )
+        aErrorHandler( DRCE_PADSTACK, _( "BGA property is for SMD pads" ) );
+
+    if( GetProperty() == PAD_PROP::MECHANICAL && GetAttribute() != PAD_ATTRIB::PTH )
+        aErrorHandler( DRCE_PADSTACK, _( "Mechanical property is for PTH pads" ) );
+
+    if( GetShape() == PAD_SHAPE::ROUNDRECT )
+    {
+        if( GetRoundRectRadiusRatio() < 0.0 )
+            aErrorHandler( DRCE_PADSTACK_INVALID, _( "(Negative corner radius is not allowed)" ) );
+        else if( GetRoundRectRadiusRatio() > 50.0 )
+            aErrorHandler( DRCE_PADSTACK, _( "Corner size will make pad circular" ) );
+    }
+    else if( GetShape() == PAD_SHAPE::CHAMFERED_RECT )
+    {
+        if( GetChamferRectRatio() < 0.0 )
+            aErrorHandler( DRCE_PADSTACK_INVALID, _( "(Negative corner chamfer is not allowed)" ) );
+        else if( GetChamferRectRatio() > 50.0 )
+            aErrorHandler( DRCE_PADSTACK_INVALID, _( "(Corner chamfer is too large)" ) );
+    }
+    else if( GetShape() == PAD_SHAPE::TRAPEZOID )
+    {
+        if(    ( GetDelta().x < 0 && GetDelta().x < -GetSize().y )
+            || ( GetDelta().x > 0 && GetDelta().x > GetSize().y )
+            || ( GetDelta().y < 0 && GetDelta().y < -GetSize().x )
+            || ( GetDelta().y > 0 && GetDelta().y > GetSize().x ) )
+        {
+            aErrorHandler( DRCE_PADSTACK_INVALID, _( "(Trapazoid delta is too large)" ) );
+        }
+    }
+
+    // PADSTACKS TODO: this will need to check each layer in the pad...
+    if( GetShape() == PAD_SHAPE::CUSTOM )
+    {
+        SHAPE_POLY_SET mergedPolygon;
+        MergePrimitivesAsPolygon( &mergedPolygon );
+
+        if( mergedPolygon.OutlineCount() > 1 )
+            aErrorHandler( DRCE_PADSTACK_INVALID, _( "(Custom pad shape must resolve to a single polygon)" ) );
+    }
+}
+
+
 bool PAD::operator==( const BOARD_ITEM& aOther ) const
 {
     if( Type() != aOther.Type() )

pcbnew/pad.h

@@ -814,6 +814,10 @@ public:
         m_zoneLayerOverrides.at( aLayer ) = aOverride;
     }
 
+    void CheckPad( UNITS_PROVIDER* aUnitsProvider,
+                   const std::function<void( int aErrorCode,
+                                             const wxString& aMsg )>& aErrorHandler ) const;
+
     double Similarity( const BOARD_ITEM& aOther ) const override;
 
     bool operator==( const BOARD_ITEM& aOther ) const override;