introduce macro `IGNORE(x)', which shall used to mark unused parameters

ChangeLog

@@ -1,3 +1,9 @@
+2010-11-16  Robert Larice
+ * src/include/ngspice.h :
+    introduce macro `IGNORE(x)', which shall used to mark unused parameters
+      for better visibility in the source code
+      and to swallow compiler warnings
+
 2010-11-14  Holger Vogt
  * inpcom.c: bug no. 3072940
 

src/include/ngspice.h

@@ -245,5 +245,8 @@ extern int tcl_fprintf(FILE *f, const char *format, ...);
 
 #endif
 
+/* macro to ignore unused variables and parameters */
+#define IGNORE(x)  (void)x
+
 
 #endif /* NGSPICE_H_INCLUDED */