Supress -Wfloat-equal on intended float comparisions

[Finkman]

Suppress intended float comparison on float values.
gcc 9.3 was complaining with "-Wfloat-equal" which is muted.

Fixes #2909

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[coveralls]

Coverage remained the same at 100.0% when pulling 3f5545f on Finkman:develop into eb488bb on nlohmann:develop.

[nlohmann]

Don't you need to also suppress the same warning in

friend bool operator==(const_reference lhs, const_reference rhs) noexcept

?

[Finkman]

Yes! My compiler did not instantiate that template. I even found one more line that needs a suppression.

[nlohmann]

You may also want to check if you now can remove the suppressions in the test suites, because these warnings are now suppressed right in the header:

$ grep "float-e" test/src/*
unit-cbor.cpp:DOCTEST_GCC_SUPPRESS_WARNING("-Wfloat-equal")
unit-constructor1.cpp:DOCTEST_GCC_SUPPRESS_WARNING("-Wfloat-equal")
unit-readme.cpp:DOCTEST_GCC_SUPPRESS_WARNING("-Wfloat-equal")
unit-reference_access.cpp:DOCTEST_GCC_SUPPRESS_WARNING("-Wfloat-equal")
unit-regression1.cpp:DOCTEST_GCC_SUPPRESS_WARNING("-Wfloat-equal")
unit-regression2.cpp:DOCTEST_GCC_SUPPRESS_WARNING("-Wfloat-equal")

[Finkman]

done.
Apologize that I am not that familiar with your workspace. 😢

[nlohmann]

Looks good to me.

[nlohmann]

Thanks!