Consistent use of 'override' for virtual methods in derived classes.

o Not all derived methods were marked 'override', but it is a great
  feature of C++11 that we should make use of.
o While at it: touched header files got a -*- c++ -*- for emacs to
  provide support for that language.
o use YS_OVERRIDE for all override keywords (though we should probably
  use the plain keyword going forward now that C++11 is established)

28 files changed, 62 insertions, 62 deletions

diff --git a/passes/techmap/abc.cc b/passes/techmap/abc.cc
index 18868c6d7..d2d15a4a9 100644
--- a/passes/techmap/abc.cc
+++ b/passes/techmap/abc.cc
@@ -1248,7 +1248,7 @@ void abc_module(RTLIL::Design *design, RTLIL::Module *current_module, std::strin
 
 struct AbcPass : public Pass {
 	AbcPass() : Pass("abc", "use ABC for technology mapping") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -1420,7 +1420,7 @@ struct AbcPass : public Pass {
 		log("[1] http://www.eecs.berkeley.edu/~alanmi/abc/\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing ABC pass (technology mapping using ABC).\n");
 		log_push();
diff --git a/passes/techmap/aigmap.cc b/passes/techmap/aigmap.cc
index b9ac7aded..35df2ff79 100644
--- a/passes/techmap/aigmap.cc
+++ b/passes/techmap/aigmap.cc
@@ -25,7 +25,7 @@ PRIVATE_NAMESPACE_BEGIN
 
 struct AigmapPass : public Pass {
 	AigmapPass() : Pass("aigmap", "map logic to and-inverter-graph circuit") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		log("\n");
 		log("    aigmap [options] [selection]\n");
@@ -37,7 +37,7 @@ struct AigmapPass : public Pass {
 		log("        Enable creation of $_NAND_ cells\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		bool nand_mode = false;
 
diff --git a/passes/techmap/alumacc.cc b/passes/techmap/alumacc.cc
index 95be7ab3b..dc7d416b0 100644
--- a/passes/techmap/alumacc.cc
+++ b/passes/techmap/alumacc.cc
@@ -539,7 +539,7 @@ struct AlumaccWorker
 
 struct AlumaccPass : public Pass {
 	AlumaccPass() : Pass("alumacc", "extract ALU and MACC cells") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -549,7 +549,7 @@ struct AlumaccPass : public Pass {
 		log("and $macc cells.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing ALUMACC pass (create $alu and $macc cells).\n");
 
diff --git a/passes/techmap/attrmap.cc b/passes/techmap/attrmap.cc
index dec81d216..0b5576b06 100644
--- a/passes/techmap/attrmap.cc
+++ b/passes/techmap/attrmap.cc
@@ -81,7 +81,7 @@ struct AttrmapAction {
 
 struct AttrmapTocase : AttrmapAction {
 	string name;
-	virtual bool apply(IdString &id, Const&) {
+	bool apply(IdString &id, Const&) YS_OVERRIDE {
 		if (match_name(name, id, true))
 			id = RTLIL::escape_id(name);
 		return true;
@@ -90,7 +90,7 @@ struct AttrmapTocase : AttrmapAction {
 
 struct AttrmapRename : AttrmapAction {
 	string old_name, new_name;
-	virtual bool apply(IdString &id, Const&) {
+	bool apply(IdString &id, Const&) YS_OVERRIDE {
 		if (match_name(old_name, id))
 			id = RTLIL::escape_id(new_name);
 		return true;
@@ -101,7 +101,7 @@ struct AttrmapMap : AttrmapAction {
 	bool imap;
 	string old_name, new_name;
 	string old_value, new_value;
-	virtual bool apply(IdString &id, Const &val) {
+	bool apply(IdString &id, Const &val) YS_OVERRIDE {
 		if (match_name(old_name, id) && match_value(old_value, val, true)) {
 			id = RTLIL::escape_id(new_name);
 			val = make_value(new_value);
@@ -112,7 +112,7 @@ struct AttrmapMap : AttrmapAction {
 
 struct AttrmapRemove : AttrmapAction {
 	string name, value;
-	virtual bool apply(IdString &id, Const &val) {
+	bool apply(IdString &id, Const &val) YS_OVERRIDE {
 		return !(match_name(name, id) && match_value(value, val));
 	}
 };
@@ -144,7 +144,7 @@ void attrmap_apply(string objname, vector<std::unique_ptr<AttrmapAction>> &actio
 
 struct AttrmapPass : public Pass {
 	AttrmapPass() : Pass("attrmap", "renaming attributes") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -179,7 +179,7 @@ struct AttrmapPass : public Pass {
 		log("            -imap keep=\"false\" keep=0 -remove keep=0\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing ATTRMAP pass (move or copy attributes).\n");
 
diff --git a/passes/techmap/attrmvcp.cc b/passes/techmap/attrmvcp.cc
index 1537def00..e59aa6518 100644
--- a/passes/techmap/attrmvcp.cc
+++ b/passes/techmap/attrmvcp.cc
@@ -25,7 +25,7 @@ PRIVATE_NAMESPACE_BEGIN
 
 struct AttrmvcpPass : public Pass {
 	AttrmvcpPass() : Pass("attrmvcp", "move or copy attributes from wires to driving cells") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		log("\n");
 		log("    attrmvcp [options] [selection]\n");
@@ -53,7 +53,7 @@ struct AttrmvcpPass : public Pass {
 		log("        multiple times.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing ATTRMVCP pass (move or copy attributes).\n");
 
diff --git a/passes/techmap/deminout.cc b/passes/techmap/deminout.cc
index 0b8fd5246..9f0c7bf67 100644
--- a/passes/techmap/deminout.cc
+++ b/passes/techmap/deminout.cc
@@ -25,7 +25,7 @@ PRIVATE_NAMESPACE_BEGIN
 
 struct DeminoutPass : public Pass {
 	DeminoutPass() : Pass("deminout", "demote inout ports to input or output") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		log("\n");
 		log("    deminout [options] [selection]\n");
@@ -33,7 +33,7 @@ struct DeminoutPass : public Pass {
 		log("\"Demote\" inout ports to input or output ports, if possible.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing DEMINOUT pass (demote inout ports to input or output).\n");
 
diff --git a/passes/techmap/dff2dffe.cc b/passes/techmap/dff2dffe.cc
index 4d515f174..3291f5a4a 100644
--- a/passes/techmap/dff2dffe.cc
+++ b/passes/techmap/dff2dffe.cc
@@ -253,7 +253,7 @@ struct Dff2dffeWorker
 
 struct Dff2dffePass : public Pass {
 	Dff2dffePass() : Pass("dff2dffe", "transform $dff cells to $dffe cells") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -284,7 +284,7 @@ struct Dff2dffePass : public Pass {
 		log("        $_DFFE_[NP]_.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing DFF2DFFE pass (transform $dff to $dffe where applicable).\n");
 
diff --git a/passes/techmap/dff2dffs.cc b/passes/techmap/dff2dffs.cc
index 0bfbdc965..39a4f6ade 100644
--- a/passes/techmap/dff2dffs.cc
+++ b/passes/techmap/dff2dffs.cc
@@ -26,7 +26,7 @@ PRIVATE_NAMESPACE_BEGIN
 
 struct Dff2dffsPass : public Pass {
 	Dff2dffsPass() : Pass("dff2dffs", "process sync set/reset with SR over CE priority") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		log("\n");
 		log("    dff2dffs [options] [selection]\n");
@@ -35,7 +35,7 @@ struct Dff2dffsPass : public Pass {
 		log("dff2dffe for SR over CE priority.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing dff2dffs pass (merge synchronous set/reset into FF cells).\n");
 
diff --git a/passes/techmap/dffinit.cc b/passes/techmap/dffinit.cc
index 6a8a86383..a8eecc970 100644
--- a/passes/techmap/dffinit.cc
+++ b/passes/techmap/dffinit.cc
@@ -25,7 +25,7 @@ PRIVATE_NAMESPACE_BEGIN
 
 struct DffinitPass : public Pass {
 	DffinitPass() : Pass("dffinit", "set INIT param on FF cells") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -44,7 +44,7 @@ struct DffinitPass : public Pass {
 		log("        mode.)\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing DFFINIT pass (set INIT param on FF cells).\n");
 
diff --git a/passes/techmap/dfflibmap.cc b/passes/techmap/dfflibmap.cc
index 5ccb770c4..416ed2bd5 100644
--- a/passes/techmap/dfflibmap.cc
+++ b/passes/techmap/dfflibmap.cc
@@ -537,7 +537,7 @@ static void dfflibmap(RTLIL::Design *design, RTLIL::Module *module, bool prepare
 
 struct DfflibmapPass : public Pass {
 	DfflibmapPass() : Pass("dfflibmap", "technology mapping of flip-flops") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		log("\n");
 		log("    dfflibmap [-prepare] -liberty <file> [selection]\n");
@@ -553,7 +553,7 @@ struct DfflibmapPass : public Pass {
 		log("liberty file.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing DFFLIBMAP pass (mapping DFF cells to sequential cells from liberty file).\n");
 
diff --git a/passes/techmap/dffsr2dff.cc b/passes/techmap/dffsr2dff.cc
index 0d4d53627..086a1d2fa 100644
--- a/passes/techmap/dffsr2dff.cc
+++ b/passes/techmap/dffsr2dff.cc
@@ -176,7 +176,7 @@ void adff_worker(SigMap &sigmap, Module *module, Cell *cell)
 
 struct Dffsr2dffPass : public Pass {
 	Dffsr2dffPass() : Pass("dffsr2dff", "convert DFFSR cells to simpler FF cell types") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -186,7 +186,7 @@ struct Dffsr2dffPass : public Pass {
 		log("$_DFF_???_) to simpler FF cell types when any of the set/reset inputs is unused.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing DFFSR2DFF pass (mapping DFFSR cells to simpler FFs).\n");
 
diff --git a/passes/techmap/extract.cc b/passes/techmap/extract.cc
index 71e29c60b..fff90f13c 100644
--- a/passes/techmap/extract.cc
+++ b/passes/techmap/extract.cc
@@ -352,7 +352,7 @@ bool compareSortNeedleList(RTLIL::Module *left, RTLIL::Module *right)
 
 struct ExtractPass : public Pass {
 	ExtractPass() : Pass("extract", "find subcircuits and replace them with cells") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -440,7 +440,7 @@ struct ExtractPass : public Pass {
 		log("See 'help techmap' for a pass that does the opposite thing.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing EXTRACT pass (map subcircuits to cells).\n");
 		log_push();
diff --git a/passes/techmap/extract_counter.cc b/passes/techmap/extract_counter.cc
index af0eb852a..a8d0bc834 100644
--- a/passes/techmap/extract_counter.cc
+++ b/passes/techmap/extract_counter.cc
@@ -559,7 +559,7 @@ void counter_worker(
 
 struct ExtractCounterPass : public Pass {
 	ExtractCounterPass() : Pass("extract_counter", "Extract GreenPak4 counter cells") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -578,7 +578,7 @@ struct ExtractCounterPass : public Pass {
 		log("\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing EXTRACT_COUNTER pass (find counters in netlist).\n");
 
diff --git a/passes/techmap/extract_fa.cc b/passes/techmap/extract_fa.cc
index a68cc5e2e..9e6dc0d24 100644
--- a/passes/techmap/extract_fa.cc
+++ b/passes/techmap/extract_fa.cc
@@ -531,7 +531,7 @@ struct ExtractFaWorker
 
 struct ExtractFaPass : public Pass {
 	ExtractFaPass() : Pass("extract_fa", "find and extract full/half adders") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -553,7 +553,7 @@ struct ExtractFaPass : public Pass {
 		log("        Verbose output\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		ExtractFaConfig config;
 
diff --git a/passes/techmap/extract_reduce.cc b/passes/techmap/extract_reduce.cc
index cc21c8665..519cad55c 100644
--- a/passes/techmap/extract_reduce.cc
+++ b/passes/techmap/extract_reduce.cc
@@ -33,7 +33,7 @@ struct ExtractReducePass : public Pass
 
 	ExtractReducePass() : Pass("extract_reduce", "converts gate chains into $reduce_* cells") { }
 
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -62,7 +62,7 @@ struct ExtractReducePass : public Pass
 				(cell->type == "$_XOR_" && gt == GateType::Xor);
 	}
 
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing EXTRACT_REDUCE pass.\n");
 		log_push();
diff --git a/passes/techmap/hilomap.cc b/passes/techmap/hilomap.cc
index 82cecac26..9ec651aef 100644
--- a/passes/techmap/hilomap.cc
+++ b/passes/techmap/hilomap.cc
@@ -55,7 +55,7 @@ void hilomap_worker(RTLIL::SigSpec &sig)
 
 struct HilomapPass : public Pass {
 	HilomapPass() : Pass("hilomap", "technology mapping of constant hi- and/or lo-drivers") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		log("\n");
 		log("    hilomap [options] [selection]\n");
@@ -74,7 +74,7 @@ struct HilomapPass : public Pass {
 		log("        each constant bit.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing HILOMAP pass (mapping to constant drivers).\n");
 
diff --git a/passes/techmap/insbuf.cc b/passes/techmap/insbuf.cc
index aa81468dc..2173049b4 100644
--- a/passes/techmap/insbuf.cc
+++ b/passes/techmap/insbuf.cc
@@ -25,7 +25,7 @@ PRIVATE_NAMESPACE_BEGIN
 
 struct InsbufPass : public Pass {
 	InsbufPass() : Pass("insbuf", "insert buffer cells for connected wires") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		log("\n");
 		log("    insbuf [options] [selection]\n");
@@ -37,7 +37,7 @@ struct InsbufPass : public Pass {
 		log("        call to \"clean\" will remove all $_BUF_ in the design.)\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing INSBUF pass (insert buffer cells for connected wires).\n");
 
diff --git a/passes/techmap/iopadmap.cc b/passes/techmap/iopadmap.cc
index 690ba87ed..efcc082d5 100644
--- a/passes/techmap/iopadmap.cc
+++ b/passes/techmap/iopadmap.cc
@@ -34,7 +34,7 @@ void split_portname_pair(std::string &port1, std::string &port2)
 
 struct IopadmapPass : public Pass {
 	IopadmapPass() : Pass("iopadmap", "technology mapping of i/o pads (or buffers)") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		log("\n");
 		log("    iopadmap [options] [selection]\n");
@@ -78,7 +78,7 @@ struct IopadmapPass : public Pass {
 		log("Tristate PADS (-toutpad, -tinoutpad) always operate in -bits mode.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing IOPADMAP pass (mapping inputs/outputs to IO-PAD cells).\n");
 
diff --git a/passes/techmap/lut2mux.cc b/passes/techmap/lut2mux.cc
index 2bb0bd8b4..d32bbff14 100644
--- a/passes/techmap/lut2mux.cc
+++ b/passes/techmap/lut2mux.cc
@@ -56,7 +56,7 @@ int lut2mux(Cell *cell)
 
 struct Lut2muxPass : public Pass {
 	Lut2muxPass() : Pass("lut2mux", "convert $lut to $_MUX_") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -65,7 +65,7 @@ struct Lut2muxPass : public Pass {
 		log("This pass converts $lut cells to $_MUX_ gates.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing LUT2MUX pass (convert $lut to $_MUX_).\n");
 
diff --git a/passes/techmap/maccmap.cc b/passes/techmap/maccmap.cc
index 32569d076..3e8e59e6b 100644
--- a/passes/techmap/maccmap.cc
+++ b/passes/techmap/maccmap.cc
@@ -365,7 +365,7 @@ PRIVATE_NAMESPACE_BEGIN
 
 struct MaccmapPass : public Pass {
 	MaccmapPass() : Pass("maccmap", "mapping macc cells") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -375,7 +375,7 @@ struct MaccmapPass : public Pass {
 		log("is used then the $macc cell is mapped to $add, $sub, etc. cells instead.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		bool unmap_mode = false;
 
diff --git a/passes/techmap/muxcover.cc b/passes/techmap/muxcover.cc
index 1dc649587..12da9ed0c 100644
--- a/passes/techmap/muxcover.cc
+++ b/passes/techmap/muxcover.cc
@@ -561,7 +561,7 @@ struct MuxcoverWorker
 
 struct MuxcoverPass : public Pass {
 	MuxcoverPass() : Pass("muxcover", "cover trees of MUX cells with wider MUXes") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -579,7 +579,7 @@ struct MuxcoverPass : public Pass {
 		log("        less efficient than the original circuit.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing MUXCOVER pass (mapping to wider MUXes).\n");
 
diff --git a/passes/techmap/nlutmap.cc b/passes/techmap/nlutmap.cc
index f1a41cc3e..cc765d89c 100644
--- a/passes/techmap/nlutmap.cc
+++ b/passes/techmap/nlutmap.cc
@@ -129,7 +129,7 @@ struct NlutmapWorker
 
 struct NlutmapPass : public Pass {
 	NlutmapPass() : Pass("nlutmap", "map to LUTs of different sizes") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -149,7 +149,7 @@ struct NlutmapPass : public Pass {
 		log("to generic logic gates ($_AND_, etc.).\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		NlutmapConfig config;
 
diff --git a/passes/techmap/pmuxtree.cc b/passes/techmap/pmuxtree.cc
index c626dbcc5..b7a22dc3b 100644
--- a/passes/techmap/pmuxtree.cc
+++ b/passes/techmap/pmuxtree.cc
@@ -67,7 +67,7 @@ static SigSpec recursive_mux_generator(Module *module, const SigSpec &sig_data,
 
 struct PmuxtreePass : public Pass {
 	PmuxtreePass() : Pass("pmuxtree", "transform $pmux cells to trees of $mux cells") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -76,7 +76,7 @@ struct PmuxtreePass : public Pass {
 		log("This pass transforms $pmux cells to a trees of $mux cells.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing PMUXTREE pass.\n");
 
diff --git a/passes/techmap/shregmap.cc b/passes/techmap/shregmap.cc
index 6936b499e..f20863ba0 100644
--- a/passes/techmap/shregmap.cc
+++ b/passes/techmap/shregmap.cc
@@ -391,7 +391,7 @@ struct ShregmapWorker
 
 struct ShregmapPass : public Pass {
 	ShregmapPass() : Pass("shregmap", "map shift registers") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -449,7 +449,7 @@ struct ShregmapPass : public Pass {
 		log("        map to greenpak4 shift registers.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		ShregmapOptions opts;
 		string clkpol, enpol;
diff --git a/passes/techmap/simplemap.cc b/passes/techmap/simplemap.cc
index c6b932bdc..660b60601 100644
--- a/passes/techmap/simplemap.cc
+++ b/passes/techmap/simplemap.cc
@@ -575,7 +575,7 @@ PRIVATE_NAMESPACE_BEGIN
 
 struct SimplemapPass : public Pass {
 	SimplemapPass() : Pass("simplemap", "mapping simple coarse-grain cells") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -590,7 +590,7 @@ struct SimplemapPass : public Pass {
 		log("  $sr, $ff, $dff, $dffsr, $adff, $dlatch\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing SIMPLEMAP pass (map simple cells to gate primitives).\n");
 		extra_args(args, 1, design);
diff --git a/passes/techmap/techmap.cc b/passes/techmap/techmap.cc
index 1908ae8b5..d0e5e2236 100644
--- a/passes/techmap/techmap.cc
+++ b/passes/techmap/techmap.cc
@@ -891,7 +891,7 @@ struct TechmapWorker
 
 struct TechmapPass : public Pass {
 	TechmapPass() : Pass("techmap", "generic technology mapper") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -1022,7 +1022,7 @@ struct TechmapPass : public Pass {
 		log("essentially techmap but using the design itself as map library).\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing TECHMAP pass (map to technology primitives).\n");
 		log_push();
@@ -1141,7 +1141,7 @@ struct TechmapPass : public Pass {
 
 struct FlattenPass : public Pass {
 	FlattenPass() : Pass("flatten", "flatten design") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -1155,7 +1155,7 @@ struct FlattenPass : public Pass {
 		log("flattened by this command.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		log_header(design, "Executing FLATTEN pass (flatten design).\n");
 		log_push();
diff --git a/passes/techmap/tribuf.cc b/passes/techmap/tribuf.cc
index 03629082c..587cb9038 100644
--- a/passes/techmap/tribuf.cc
+++ b/passes/techmap/tribuf.cc
@@ -139,7 +139,7 @@ struct TribufWorker {
 
 struct TribufPass : public Pass {
 	TribufPass() : Pass("tribuf", "infer tri-state buffers") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -156,7 +156,7 @@ struct TribufPass : public Pass {
 		log("        to non-tristate logic. this option implies -merge.\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		TribufConfig config;
 
diff --git a/passes/techmap/zinit.cc b/passes/techmap/zinit.cc
index a577e1235..b46147fb9 100644
--- a/passes/techmap/zinit.cc
+++ b/passes/techmap/zinit.cc
@@ -25,7 +25,7 @@ PRIVATE_NAMESPACE_BEGIN
 
 struct ZinitPass : public Pass {
 	ZinitPass() : Pass("zinit", "add inverters so all FF are zero-initialized") { }
-	virtual void help()
+	void help() YS_OVERRIDE
 	{
 		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
 		log("\n");
@@ -37,7 +37,7 @@ struct ZinitPass : public Pass {
 		log("        also add zero initialization to uninitialized FFs\n");
 		log("\n");
 	}
-	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
 		bool all_mode = false;