Add suppression for some cppheck problems.

The files we get from GTKWave are not under our control so we need to
ignore the cppcheck style warnings for them. The random routines are
from the standard so they should not be changed to fix style warnings
either. We also have some weird, but correct pointer subtraction that
cppcheck warns about. This patch adds suppression files for all these
warnings. You must have the latest cppcheck from git since I submitted
a patch that adds the ability to place comments in the suppression file.

Makefile.in

@@ -157,7 +157,8 @@ endif
 	rm -rf autom4te.cache
 
 cppcheck: $(O:.o=.cc) $(srcdir)/dosify.c $(srcdir)/version.c
-	cppcheck --enable=all -f $(INCLUDE_PATH) $^
+	cppcheck --enable=all -f --suppressions $(srcdir)/cppcheck.sup \
+	         $(INCLUDE_PATH) $^
 
 cppcheck-all:
 	$(foreach dir,$(SUBDIRS),$(MAKE) -C $(dir) cppcheck && ) true

cppcheck.sup

@@ -0,0 +1,3 @@
+// These are correct and are used to find the base (zero) pin.
+thisSubtraction:netlist.h:4119
+thisSubtraction:netlist.h:4128

vpi/Makefile.in

@@ -87,7 +87,8 @@ distclean: clean
 	rm -f vpi_config.h stamp-vpi_config-h
 
 cppcheck: $(O:.o=.c) $(OPP:.o=.cc) $(M:.o=.c) $(V:.o=.c)
-	cppcheck --enable=all -f $(INCLUDE_PATH) $^
+	cppcheck --enable=all -f --suppressions $(srcdir)/cppcheck.sup \
+	         $(INCLUDE_PATH) $^
 
 Makefile: $(srcdir)/Makefile.in ../config.status
 	cd ..; ./config.status --file=vpi/$@

vpi/cppcheck.sup

@@ -0,0 +1,41 @@
+// The following three files are copied directly from GTKWave and we do not
+// have control over them. Tony has a specific programming style so these
+// problems will not be fixed.
+
+// fstapi.c from GTKWave
+variableScope:fstapi.c:1485
+variableScope:fstapi.c:1602
+variableScope:fstapi.c:1642
+variableScope:fstapi.c:1643
+variableScope:fstapi.c:2336
+variableScope:fstapi.c:2651
+variableScope:fstapi.c:2655
+variableScope:fstapi.c:2656
+
+// lxt2_write.c from GTKWave
+variableScope:lxt2_write.c:63
+variableScope:lxt2_write.c:523
+variableScope:lxt2_write.c:581
+variableScope:lxt2_write.c:587
+variableScope:lxt2_write.c:1602
+variableScope:lxt2_write.c:2049
+
+// lxt_write.c from GTKWave
+variableScope:lxt_write.c:31
+variableScope:lxt_write.c:587
+variableScope:lxt_write.c:640
+variableScope:lxt_write.c:1056
+variableScope:lxt_write.c:1057
+variableScope:lxt_write.c:1058
+variableScope:lxt_write.c:1841
+variableScope:lxt_write.c:2586
+variableScope:lxt_write.c:2587
+variableScope:lxt_write.c:2588
+variableScope:lxt_write.c:2589
+
+// The routines in sys_random.c are exact copies from IEEE1364-2005 and
+// they have scope warnings that we need to ignore.
+variableScope:sys_random.c:46
+variableScope:sys_random.c:69
+variableScope:sys_random.c:92
+variableScope:sys_random.c:147