Stacked $filepathname to make #line directives in #INCLUDEs work.
[Nicholas Clark]Sprinked dVAR in with dXSARGS, for God-(Jarkko)-knows-what
reason. [Jarkko Hietaniemi]Use printf-style formats in Perl_croak() for some significant
savings in number of distinct constant strings in the linked
binaries we create. [Alexey Tourbin]Don't use 'class' as a variable name in the t/XSTest.xs module,
since that's a keyword in C++. [Jarkko Hietaniemi]