Xtensa fails to build with `error: invalid conversion from 'bool (*)(`

[sylvestre]

FAILED: lib/Target/Xtensa/CMakeFiles/LLVMXtensaCodeGen.dir/XtensaISelLowering.cpp.o
/opt/sccache//sccache /usr/bin/g++ -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/build/source/build-llvm/lib/Target/Xtensa -I/build/source/llvm/lib/Target/Xtensa -I/build/source/build-llvm/include -I/build/source/llvm/include -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wno-unused-command-line-argument -Wdate-time -D_FORTIFY_SOURCE=3 -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wno-missing-field-initializers -pedantic -Wno-long-long -Wimplicit-fallthrough -Wno-uninitialized -Wno-nonnull -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wno-misleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -fdebug-prefix-map=/build/source/build-llvm=../ -fdebug-prefix-map=/build/source/= -no-canonical-prefixes -ffile-prefix-map=/build/source/build-llvm=../ -ffile-prefix-map=/build/source/= -no-canonical-prefixes -O3 -DNDEBUG -std=c++17 -fvisibility=hidden  -fno-exceptions -funwind-tables -MD -MT lib/Target/Xtensa/CMakeFiles/LLVMXtensaCodeGen.dir/XtensaISelLowering.cpp.o -MF lib/Target/Xtensa/CMakeFiles/LLVMXtensaCodeGen.dir/XtensaISelLowering.cpp.o.d -o lib/Target/Xtensa/CMakeFiles/LLVMXtensaCodeGen.dir/XtensaISelLowering.cpp.o -c /build/source/llvm/lib/Target/Xtensa/XtensaISelLowering.cpp
/build/source/llvm/lib/Target/Xtensa/XtensaISelLowering.cpp: In member function 'bool (* llvm::XtensaTargetLowering::CCAssignFnForCall(llvm::CallingConv::ID, bool) const)(unsigned int, llvm::MVT, llvm::MVT, llvm::CCValAssign::LocInfo, llvm::ISD::ArgFlagsTy, llvm::Type*, llvm::CCState&)':
/build/source/llvm/lib/Target/Xtensa/XtensaISelLowering.cpp:439:10: error: invalid conversion from 'bool (*)(unsigned int, llvm::MVT, llvm::MVT, llvm::CCValAssign::LocInfo, llvm::ISD::ArgFlagsTy, llvm::CCState&)' to 'bool (*)(unsigned int, llvm::MVT, llvm::MVT, llvm::CCValAssign::LocInfo, llvm::ISD::ArgFlagsTy, llvm::Type*, llvm::CCState&)' [-fpermissive]
  439 |   return CC_Xtensa_Custom;
      |          ^~~~~~~~~~~~~~~~
      |          |
      |          bool (*)(unsigned int, llvm::MVT, llvm::MVT, llvm::CCValAssign::LocInfo, llvm::ISD::ArgFlagsTy, llvm::CCState&)
At global scope:

very recent regression