[Bug libstdc++/77469] std::regex x("[b\\-a]") throws with message "Invalid range in bracket expression."

[alban_sf@baker-research.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77469

--- Comment #1 from alban_sf@baker-research.com ---
Created attachment 39543
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=39543&action=edit
Test program with the bug

Build the program:

  g++ testRegex.cc -o testRegex -std=c++11

Run:

  ./testRegex

Output:

  Trying:  [b\-a]
  Exception:  Invalid range in bracket expression.