Switch one PI to M_PI to support STRICT_R_HEADERS

[eddelbuettel]

Dear s2 team,

The Rcpp team is trying to move towards defining STRICT_R_HEADERS by default. Please the issue ticket at RcppCore/Rcpp#1158 for motivation and history. In late April and early May, we identified around 51 packages needing changes (which we generally sent by PR or, in case of no known git repo, emailed patch). We are thrilled to report that 38 have already made the changes, including some on CRAN. We also accomodated one first fix in Rcpp itself -- the cfloat (or float.h) header is needed for the floating limits such as DBL_MAX. A common remaining issue is use of PI.

And it appears that your most recent package change introduced a mild regression. One line of code refers to PI where M_PI would make us whole. This PR changes this. It also adds a define for STRICT_R_HEADERS to test this, you are more than welcome to remove that define or place it elsewhere. I can also remove it from the PR if you like.

As discussed in RcppCore/Rcpp#1158, this is not urgent, but we of course welcome relatively prompt resolution at CRAN so when we continue to test for this (at a likely montly pace) so we do not get false positives as we will continue to use the CRAN set of packages (as opposed to hand-curated set of upstream dev versions).

Many thanks for your help, and I hope you continue to find Rcpp helpful. Please don't hesitate to ask if you have any questions.

[codecov-commenter]

Codecov Report

Merging #118 (d5cbc99) into master (6e344ad) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #118   +/-   ##
=======================================
  Coverage   94.04%   94.04%           
=======================================
  Files          40       40           
  Lines        2987     2987           
=======================================
  Hits         2809     2809           
  Misses        178      178           

Impacted Files	Coverage Δ
src/s2-transformers.cpp	96.70% <100.00%> (ø)

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[edzer]

Thanks a lot, Dirk!

[eddelbuettel]

Thanks for the speedy turnaround!