Without this, the VMS compiler, with warnings cranked up to level 4,
emits pages and pages of things like:
dVAR;
....^
%CC-I-NOPARMLIST, The declaration of the function Perl___notused has
an empty parameter list. If the function has parameters, they should
be declared here; if it has no parameters, "void" should be specified
in the parameter list.
at line number 100 in file MDA0:[SMOKE.blead]perl.c;1
Over 2,000 of these plus other warnings yields a smoke report of 750K,
which is quite a bit over the 400K limit of the perl.org mailing lists,
not to mention being a slow read.
/* Rats: if dTHR is just blank then the subsequent ";" throws an error */
/* Declaring a *function*, instead of a variable, ensures that we don't rely
on being able to suppress "unused" warnings. */
-#define dNOOP extern int Perl___notused()
+#define dNOOP extern int Perl___notused(void)
#ifndef pTHX
/* Don't bother defining tTHX and sTHX; using them outside