fix deprecated-copy warnings: add assignment operators
Elango built ICU4C with gcc 9.2 and -fsanitize=undefined and got several warnings about assignment operators that are used, and implicitly provided by the compiler, but where only copy constructors are explicitly defined.
We should explicitly define the corresponding assignment operators, too.
Two of the classes are internal:
One is public:
Since the compiler has been implicitly providing the assignment operator, I think we should add it as @stable ICU 4.2.
Example compiler warning:
I re-ran the GCC build on maint/maint-67 with the same -fsanitize=undefined flags, and I can verify the desired absence of warnings about the implicit assignment operator.
I did a diff between the output of the make command in the before & after (maint/maint-67) branches just to be extra sure. I saved and uploaded the diff file, just in case.
could you please re-run the gcc -fsanitize=undefined build on the maint/maint-67 branch code and double-check that 's recent PR fixed this issue?