V0.9: Update lex/yacc builds to be consistent and to support parallel builds

Not all the lex/yacc (flex/bison) targets were using a consistent syntax.
This patch fixes that and explicitly serializes the *.c/*.cc and *.h build.
Not doing this was causing problem when using make -j. The issue appears to
be that if two targets are specified for a rule (e.g. file.cc file.h: file.y)
make does not realize they are both built by the same call so the rule is
executed twice. Once for the .cc target and once for the .h target. This is
not a problem for a serial build. To work around this only use the .c/.cc
file in the main target and then make the .h file depend on the .c/.cc file
as a sub-target.

Makefile.in

@@ -118,8 +118,8 @@ endif
 clean:
 	$(foreach dir,$(SUBDIRS),$(MAKE) -C $(dir) $@ && ) true
 	rm -f *.o parse.cc parse.h lexor.cc
-	rm -f ivl.exp iverilog-vpi.man iverilog-vpi.pdf iverilog-vpi.ps parse.output
-	rm -f syn-rules.output dosify.exe ivl@EXEEXT@ check.vvp
+	rm -f ivl.exp iverilog-vpi.man iverilog-vpi.pdf iverilog-vpi.ps
+	rm -f parse.output syn-rules.output dosify.exe ivl@EXEEXT@ check.vvp
 	rm -f lexor_keyword.cc libivl.a libvpi.a iverilog-vpi syn-rules.cc
 	rm -rf dep
 	rm -f version.exe
@@ -223,15 +223,17 @@ lexor.o: lexor.cc parse.h
 
 parse.o: parse.cc
 
-parse.cc parse.h: $(srcdir)/parse.y
-	$(YACC) --verbose -t -p VL -d -o parse.cc $(srcdir)/parse.y
+# Build this in two steps to avoid parallel build issues (see pr3462585)
+parse.cc: $(srcdir)/parse.y
+	$(YACC) --verbose -t -p VL -d -o $@ $<
+parse.h: parse.cc
 	mv parse.cc.h parse.h 2>/dev/null || mv parse.hh parse.h
 
 syn-rules.cc: $(srcdir)/syn-rules.y
-	$(YACC) --verbose -p syn_ -o syn-rules.cc $(srcdir)/syn-rules.y
+	$(YACC) --verbose -t -p syn_ -o $@ $<
 
 lexor.cc: $(srcdir)/lexor.lex
-	$(LEX) -PVL -s -olexor.cc $(srcdir)/lexor.lex
+	$(LEX) -PVL -s -t $< > $@
 
 lexor_keyword.o: lexor_keyword.cc parse.h
 

driver/Makefile.in

@@ -68,10 +68,12 @@ iverilog@EXEEXT@: $O
 	$(CC) $(LDFLAGS) $O -o iverilog@EXEEXT@ @EXTRALIBS@
 
 cflexor.c: cflexor.lex
-	$(LEX) -s -Pcf -ocflexor.c $(srcdir)/cflexor.lex
+	$(LEX) -Pcf -s -t $< > $@
 
-cfparse.h cfparse.c: cfparse.y
-	$(YACC) --verbose -t -d -o cfparse.c --name-prefix=cf $(srcdir)/cfparse.y
+# Build this in two steps to avoid parallel build issues (see pr3462585)
+cfparse.c: cfparse.y
+	$(YACC) --verbose -t -p cf -d -o $@ $<
+cfparse.h: cfparse.c
 
 dep:
 	mkdir dep

ivlpp/Makefile.in

@@ -61,7 +61,7 @@ ivlpp@EXEEXT@: $O
 	$(CC) $(LDFLAGS) $O -o ivlpp@EXEEXT@ @EXTRALIBS@
 
 lexor.c: lexor.lex
-	$(LEX) -olexor.c $(srcdir)/lexor.lex
+	$(LEX) -s -t $< > $@
 
 install: all installdirs $(libdir)/ivl$(suffix)/ivlpp@EXEEXT@
 

vpi/Makefile.in

@@ -87,15 +87,17 @@ system.vpi: $O ../vvp/libvpi.a
 	$(CC) @shared@ -o $@ $O -L../vvp $(LDFLAGS) -lvpi $(SYSTEM_VPI_LDFLAGS)
 
 sys_readmem_lex.c: sys_readmem_lex.lex
-	$(LEX) -t -Preadmem $(srcdir)/sys_readmem_lex.lex > sys_readmem_lex.c
+	$(LEX) -Preadmem -s -t $< > $@
 
 sdf_lexor.o: sdf_lexor.c sdf_parse.h
 
 sdf_lexor.c: sdf_lexor.lex
-	$(LEX) -t -Psdf $(srcdir)/sdf_lexor.lex > sdf_lexor.c
+	$(LEX) -Psdf -s -t $< > $@
 
-sdf_parse.c sdf_parse.h: $(srcdir)/sdf_parse.y
-	$(YACC) --verbose -d -p sdf -o sdf_parse.c $(srcdir)/sdf_parse.y
+# Build this in two steps to avoid parallel build issues (see pr3462585)
+sdf_parse.c: $(srcdir)/sdf_parse.y
+	$(YACC) --verbose -t -p sdf -d -o $@ $<
+sdf_parse.h: sdf_parse.c
 
 v2005_math.vpi: $M ../vvp/libvpi.a
 	$(CC) @shared@ -o $@ $M -L../vvp $(LDFLAGS) -lvpi $(VA_MATH_VPI_LDFLAGS)

vvp/Makefile.in

@@ -140,10 +140,9 @@ parse.o: parse.cc
 tables.o: tables.cc
 
 parse.cc: $(srcdir)/parse.y
-	$(YACC) --verbose -t -d -o parse.cc $(srcdir)/parse.y
-
+	$(YACC) --verbose -t -d -o $@ $<
 parse.h: parse.cc
-	mv parse.cc.h parse.h 2>/dev/null || mv parse.hh parse.h
+	mv parse.cc.h $@ 2>/dev/null || mv parse.hh $@
 
 lexor.cc: $(srcdir)/lexor.lex
 	$(LEX) -s -olexor.cc $(srcdir)/lexor.lex