Fix ambiguous call of constexpr variables

What is the bug

Some compilers (for example, Apple clang, LLVM clang) cannot figure out the constexpr members of a templated class if they are not specialized.

How do you fix it

Use specialized member references instead of this.

How urgent is the bugfix

• I need it as soon as possible
• I can wait for a couple of days
• None of my current code is directly affected

Mandatory steps before review

• Gitlab CI passes (Hint: use make format for linting)
• Bugfix is covered by additional unit tests
• Mark the merge request as ready by removing Draft:

Mandatory steps before merge

• Reviewed by a maintainer
• Incorporate review suggestions
• Remember to edit the commit message and select the proper changelog category (feature/bugfix/other)
• Prior to merging, please remove any boilerplate from the MR description, retaining only the What is the bug and How do you fix it section to maintain

You are not supposed to merge this request by yourself, the maintainers of libiconmath take care of this action!

requested review from @k202170

assigned to @b382190

Just realize that we don't have a .clang-format yet. I will work on that.

marked this merge request as draft

marked the checklist item Mark the merge request as ready by removing Draft: as incomplete

added 1 commit

• 3bb732d1 - Add LD_LIBRARY_PATH

Compare with previous version

This can wait for !46 (merged).

marked the checklist item I can wait for a couple of days as completed

marked the checklist item I need it as soon as possible as incomplete

added C++ improvement label

changed the description

added 45 commits

• 3bb732d1...7e72fd0c - 44 commits from branch feature-add-cpp-codes
• c5aaa8fb - Fix ambiguous call of constexpr variables

Compare with previous version

added 1 commit

• c520667a - Revert style changes

Compare with previous version

marked the checklist item I need it as soon as possible as completed

marked the checklist item I can wait for a couple of days as incomplete

marked this merge request as ready

marked the checklist item Mark the merge request as ready by removing Draft: as completed

marked the checklist item Reviewed by a maintainer as completed

marked the checklist item Remember to edit the commit message and select the proper changelog category (feature/bugfix/other) as completed

marked the checklist item Prior to merging, please remove any boilerplate from the MR description, retaining only the What is the bug and How do you fix it section to maintain as completed

enabled an automatic merge when all merge checks for c520667a pass

merged

mentioned in commit 62c21c2a