Devel::NYTProf is a powerful feature-rich source code profiler for Perl. (Mostly in maintenance mode, so PRs are much more likely to be acted upon than Issues.)
cpp (Loc.U):
This variable is used internally by Configure to determine the
full pathname (if any) of the cpp program. After Configure runs,
the value is reset to a plain "cpp" and is not useful.
...
cpprun (cppstdin.U):
This variable contains the command which will invoke a C preprocessor
on standard input and put the output to stdout. It is guaranteed not
to be a wrapper and may be a null string if no preprocessor can be
made directly available. This preprocessor might be different from the
one used by the C compiler. Don't forget to append cpplast after the
preprocessor options.
See https://github.com/Perl/perl5/issues/17948
We've locally got perl configured with
-Dcpp=$GCC -E
, which is a perfectly valid C PreProcessor.However,
cpp
only contains the "path" aspect of that, and strips the arguments.https://github.com/Perl/perl5/blob/48a788454f1719093d08e80bbb70723ae345163a/Porting/Glossary#L315-L350