devel/llvm15: fix build with clang 21
Recent versions of clang complain about explicit copy constructors,
leading to errors similar to:
/wrkdirs/usr/ports/devel/llvm15/work-default/llvm-project-15.0.7.src/llvm/tools/sancov/sancov.cpp:532:44: error: chosen constructor is explicit in copy-initialization
532 | return SpecialCaseList::createOrDie({{ClBlacklist}},
| ^~~~~~~~~~~~~
/usr/include/c++/v1/string:1153:64: note: explicit constructor declared here
1153 | _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit basic_string(const _Tp& __t) {
| ^
/usr/include/c++/v1/__vector/vector.h:276:91: note: passing argument to parameter '__il' here
276 | _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector(initializer_list<value_type> __il) {
| ^
/wrkdirs/usr/ports/devel/llvm15/work-default/llvm-project-15.0.7.src/llvm/tools/sancov/sancov.cpp:535:42: error: chosen constructor is explicit in copy-initialization
535 | return SpecialCaseList::createOrDie({{ClIgnorelist}},
| ^~~~~~~~~~~~~~
/usr/include/c++/v1/string:1153:64: note: explicit constructor declared here
1153 | _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit basic_string(const _Tp& __t) {
| ^
/usr/include/c++/v1/__vector/vector.h:276:91: note: passing argument to parameter '__il' here
276 | _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector(initializer_list<value_type> __il) {
| ^In this case, ClBlacklist and ClIgnoreList are instances of
cl::opt, not a std::string as expected. Use getValue() to get the
actual std::string values.
PR: 292111
Approved by: brooks (maintainer)
MFH: 2026Q1