compiler warning from DataFrame.h when including Rcpp

[kevinushey]

I saw this while compiling reticulate with latest Rcpp on macOS:

In file included from python.cpp:4:
In file included from /Users/kevinushey/Library/R/4.0/library/Rcpp/include/Rcpp.h:57:
/Users/kevinushey/Library/R/4.0/library/Rcpp/include/Rcpp/DataFrame.h:136:18: warning: unused variable 'data' [-Wunused-variable]
            SEXP data = Parent::get__();
                 ^

And indeed, data is read but never used here:

Rcpp/inst/include/Rcpp/DataFrame.h

Lines 133 to 155 in 0ba1b55

	void set_type_after_push(){
	int max_rows = 0;
	bool invalid_column_size = false;
	SEXP data = Parent::get__();
	List::iterator it;
	// Get the maximum number of rows
	for (it = Parent::begin(); it != Parent::end(); ++it) {
	if (Rf_xlength(*it) > max_rows) {
	max_rows = Rf_xlength(*it);
	}
	}
	for (it = Parent::begin(); it != Parent::end(); ++it) {
	if (Rf_xlength(*it) == 0 || ( Rf_xlength(*it) > 1 && max_rows % Rf_xlength(*it) != 0 )) {
	// We have a column that is not an integer fraction of the largest
	invalid_column_size = true;
	}
	}
	if (invalid_column_size) {
	warning("Column sizes are not equal in DataFrame::push_back, object degrading to List\n");
	} else {
	set__(Parent::get__());
	}
	}

Looks like it was introduced with d800e2a. I think we can just remove the offending line.

[eddelbuettel]

Interesting. Yes, that is new (in 1.0.6) code by @waltersom that hasn't seen too much exposure yet as 1.0.6 is new-ish.

It does look like we can trim it off. Thoughts, @waltersom? No need for a PR we can clean it up alongside whatever comes up next.

[waltersom]

I agree, should be fine to remove, I guess it was part of an earlier attempt by me that should have been taken out earlier.

…

On Thu, Jan 21, 2021, 08:23 Dirk Eddelbuettel ***@***.***> wrote: Interesting. Yes, that is new (in 1.0.6) code by @waltersom <https://github.com/waltersom> that hasn't seen too much exposure yet as 1.0.6 is new-ish. It does look like we can trim it off. Thoughs, @waltersom <https://github.com/waltersom>? No need for a PR we can clean it up alongside whatever comes up next. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#1137 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AA7W2M7FZYH54IH2XAE33YDS24URHANCNFSM4WLEKFAQ> .