Turn the charAttributeFunction array of function pointers into a switch. This has two benefits: - The compiler now warns when we introduce a new QChar::Script value and statically forces us to think whether a new attribute handling function is needed. - A table of function pointers requires relocations. A switch might not. GCC uses a jump table to implement this switch, jumping to distinct lea instructions fetching distinct function pointer values, and thereby removes relocations, while Clang actually forms a function pointer table and turns the switch into an indexing operation (with compiler-generated guards). I didn't check whether Clang's table actually requires relocations, relinfo.pl doesn't report any reductions, but it's become unreliable over the years, because it doesn't for GCC, either. Difference: qunicodetools.cpp.o: - 0000000000000000 l O .data.rel.ro.local 0000000000000108 QUnicodeTools::Tailored::charAttributeFunction 0000000000000000 l d .data.rel.ro.local 0000000000000000 .data.rel.ro.local See https://stackoverflow.com/questions/19067010/finding-where-relocations-originate/19338343#19338343 for the script to generate this output. See https://www.akkadia.org/drepper/dsohowto.pdf Section 1.6 for why we care. Instead of collapsing identical return statements from adjacent case statements into one, keep the per-case return statements for now, to aid review, and clean up in a follow-up commit. Amends dd7d8304bbe599320b163b94e9a4ad9a6f35b740. Pick-to: 6.9 6.8 6.5 Task-number: QTBUG-100536 Change-Id: Ic5b6bd29e3a3a88f0d194fa7d76272a4770b9840 Reviewed-by: Marc Mutz <marc.mutz@qt.io> Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>