error: implicit instantiation of undefined template 'fmt::detail::type_is_unformattable_for<Gaffer::TweakPlug::Mode, char>'

[Martinfx]

Hi,
i have issue in last commit in git. Do you know please how to fix ?
libfmt: libfmt-12.1.0

/usr/local/llvm19/bin/clang++ -o src/GafferBindings/Serialisation.os -c "-O2 -pipe -fstack-protector-strong -isystem /usr/local/include -fno-strict-aliasing -isystem /usr/local/include " -isystem /home/maxfx/Documents/FreeBSD-Ports/gaffer/work/gaffer-611d062a6e73af4449395f98c1fbf1bddbb3e1e5/build/gaffer-1.7.0.0-linux/include -isystem /home/maxfx/Documents/FreeBSD-Ports/gaffer/work/gaffer-611d062a6e73af4449395f98c1fbf1bddbb3e1e5/build/gaffer-1.7.0.0-linux/include/Imath -isystem /home/maxfx/Documents/FreeBSD-Ports/gaffer/work/gaffer-611d062a6e73af4449395f98c1fbf1bddbb3e1e5/build/gaffer-1.7.0.0-linux/include/GL -isystem /usr/local/include -Wno-unused-local-typedef -Wno-unused-parameter -std=c++17 -fvisibility=hidden -DNDEBUG -DBOOST_DISABLE_ASSERTS -O3 -DGafferBindings_EXPORTS -fPIC -DBOOST_FILESYSTEM_VERSION=3 -DBOOST_FILESYSTEM_NO_DEPRECATED -DBOOST_PYTHON_MAX_ARITY=20 -Iinclude -I/usr/local/include -I/usr/local/include/qt5 -I/usr/local/include/python3.11 -I/usr/local/include/Imath -I/usr/local/include/oneapi -I/usr/local/include/freetype2 -I/usr/local/include/utils -I/usr/local/include/third_party/atomic -I/usr/local/share/openshadinglanguage/shaders -Ibuild/gaffer-1.7.0.0-linux/include/python3.11 src/GafferBindings/Serialisation.cpp
In file included from src/Gaffer/TweakPlug.cpp:37:
In file included from include/Gaffer/TweakPlug.h:40:
In file included from include/Gaffer/CompoundDataPlug.h:40:
In file included from include/Gaffer/TypedPlug.h:40:
In file included from include/Gaffer/ValuePlug.h:289:
In file included from include/Gaffer/ValuePlug.inl:37:
In file included from /usr/local/include/fmt/format.h:41:
/usr/local/include/fmt/base.h:2310:45: error: implicit instantiation of undefined template 'fmt::detail::type_is_unformattable_for<Gaffer::TweakPlug::Mode, char>'
 2310 |     type_is_unformattable_for<T, char_type> _;
      |                                             ^
/usr/local/include/fmt/base.h:2283:44: note: in instantiation of function template specialization 'fmt::detail::value<fmt::context>::value<Gaffer::TweakPlug::Mode, 0>' requested here
 2283 |   FMT_CONSTEXPR20 FMT_INLINE value(T& x) : value(x, custom_tag()) {}
      |                                            ^
/usr/local/include/fmt/format.h:4349:40: note: in instantiation of function template specialization 'fmt::detail::value<fmt::context>::value<Gaffer::TweakPlug::Mode, 0>' requested here
 4349 |   return vformat(fmt.str, vargs<T...>{{args...}});
      |                                        ^
src/Gaffer/TweakPlug.cpp:142:35: note: in instantiation of function template specialization 'fmt::format<Gaffer::TweakPlug::Mode &>' requested here
  142 |                                 throw IECore::Exception( fmt::format( "Not a valid tweak mode: {}.", mode ) );
      |                                                               ^
src/Gaffer/TweakPlug.cpp:285:10: note: in instantiation of function template specialization '(anonymous namespace)::applyNumericTweak<float>' requested here
  285 |                 return applyNumericTweak( source, tweak, mode, tweakName );
      |                        ^
src/Gaffer/TweakPlug.cpp:717:13: note: in instantiation of function template specialization '(anonymous namespace)::applyValueTweak<float>' requested here
  717 |                                 value = applyValueTweak( value, tweakDataMatchingTyped->readable(), mode, name );
      |                                         ^
src/Gaffer/TweakPlug.cpp:688:10: note: in instantiation of function template specialization 'IECore::dispatch<(lambda at src/Gaffer/TweakPlug.cpp:690:3)>' requested here
  688 |         IECore::dispatch(
      |                 ^
/usr/local/include/fmt/base.h:2150:45: note: template is declared here
 2150 | template <typename T, typename Char> struct type_is_unformattable_for;

[murraystevenson]

Hi,

We require the fairly old version of libfmt-9.1.0. Supporting the changes introduced in more modern versions of libfmt such as the removal of implicit conversions for enums in libfmt-10.0.0 would require some additional work. There were some attempts at this in #6608, but that PR hasn't seen any movement since the initial review.

[Martinfx]

ok. thank you