The static variable 'tracefile' is only used when WIN16 is defined,

so put it inside #ifdef to eliminate unused variable compiler
warning on other platforms.

nsprpub/lib/msgc/src/prgcapi.c

@@ -250,7 +250,9 @@ PR_IMPLEMENT(void) PR_GetEndFinalizeHook(GCEndFinalizeHook **hook, void **arg)
 #ifdef DEBUG
 #include "prprf.h"
 
+#if defined(WIN16)
 static FILE *tracefile = 0;
+#endif
 
 PR_IMPLEMENT(void) GCTrace(char *fmt, ...)
 {