Defensive coding to avoid 0x80000000/0xFFFFFFFF FPE

[kevinbackhouse]

This is a follow-up to #1750. Adding the same defensive code against FPEs caused by 0x80000000/0xFFFFFFFF. This code is new on the main branch.

[codecov]

Codecov Report

Merging #1751 (e4f5684) into main (695d22c) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main    #1751   +/-   ##
=======================================
  Coverage   66.94%   66.94%           
=======================================
  Files         151      151           
  Lines       20794    20794           
=======================================
  Hits        13920    13920           
  Misses       6874     6874           

Impacted Files	Coverage Δ
src/tags_int.cpp	87.20% <100.00%> (ø)

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[hassec]

LGTM 👍