legacy-support breaks a valid code: error: no match for 'operator*' (operand types are 'double' and 'std::complex<float>')

[barracuda156]

Take a look at this issue with scipy: ​https://github.com/scipy/scipy/issues/21826

Wasting a lot of time, both of scipy upstream and my own, I finally dug this out: it is legacysupport breaking this. Specifically, identical command errs out with legacysupport headers, but compiles normally without it:

36-50% sudo   /opt/local/bin/g++-mp-14 -I/opt/local/include/LegacySupport -Iscipy/special/_special_ufuncs.cpython-311-darwin.so.p -Iscipy/special -I../scipy/special -Iscipy/_lib -I../scipy/_lib -I../scipy/_build_utils/src -I../../../../../../../../Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-packages/numpy/core/include -I/opt/local/Library/Frameworks/Python.framework/Versions/3.11/include/python3.11 -fvisibility=hidden -fvisibility-inlines-hidden -fdiagnostics-color=always -DNDEBUG -Wall -Winvalid-pch -std=gnu++17 -O3 -D_GLIBCXX_USE_CXX11_ABI=0 -isysroot/ -DSP_SPECFUN_ERROR -DNPY_NO_DEPRECATED_API=NPY_1_9_API_VERSION -MD -MQ scipy/special/_special_ufuncs.cpython-311-darwin.so.p/_special_ufuncs.cpp.o -MF scipy/special/_special_ufuncs.cpython-311-darwin.so.p/_special_ufuncs.cpp.o.d -o scipy/special/_special_ufuncs.cpython-311-darwin.so.p/_special_ufuncs.cpp.o -c ../scipy/special/_special_ufuncs.cpp
In file included from ../scipy/special/special/specfun.h:4,
                 from ../scipy/special/special.h:6,
                 from ../scipy/special/_special_ufuncs.cpp:7:
../scipy/special/special/specfun/specfun.h: In instantiation of 'std::complex<_Tp> special::specfun::e1z(std::complex<_Tp>) [with T = float]':
../scipy/special/special/expint.h:17:40:   required from 'std::complex<_Tp> special::exp1(std::complex<_Tp>) [with T = float]'
   17 |     std::complex<T> outz = specfun::e1z(z);
      |                            ~~~~~~~~~~~~^~~
../scipy/special/_special_ufuncs.cpp:304:47:   required from here
  304 |          static_cast<func_F_F_t>(special::exp1), static_cast<func_D_D_t>(special::exp1)},
      |                                               ^
../scipy/special/special/specfun/specfun.h:2099:70: error: no match for 'operator*' (operand types are 'double' and 'std::complex<float>')
 2099 |             ce1 = -el - std::log(-z) + z*ce1 - copysign(pi, z.imag())*std::complex<T>(0.0, 1.0);
      |                                                ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ../scipy/special/special/error.h:27,
                 from ../scipy/special/sf_error_state.h:4,
                 from ../scipy/special/sf_error.h:3,
                 from ../scipy/special/ufunc.h:17,
                 from ../scipy/special/_special_ufuncs.cpp:1:
/opt/local/include/gcc14/c++/complex:400:5: note: candidate: 'template<class _Tp> std::complex<_Tp> std::operator*(const complex<_Tp>&, const complex<_Tp>&)'
  400 |     operator*(const complex<_Tp>& __x, const complex<_Tp>& __y)
      |     ^~~~~~~~
/opt/local/include/gcc14/c++/complex:400:5: note:   template argument deduction/substitution failed:
../scipy/special/special/specfun/specfun.h:2099:70: note:   mismatched types 'const std::complex<_Tp>' and 'double'
 2099 |             ce1 = -el - std::log(-z) + z*ce1 - copysign(pi, z.imag())*std::complex<T>(0.0, 1.0);
      |                                                ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
/opt/local/include/gcc14/c++/complex:409:5: note: candidate: 'template<class _Tp> std::complex<_Tp> std::operator*(const complex<_Tp>&, const _Tp&)'
  409 |     operator*(const complex<_Tp>& __x, const _Tp& __y)
      |     ^~~~~~~~
/opt/local/include/gcc14/c++/complex:409:5: note:   template argument deduction/substitution failed:
../scipy/special/special/specfun/specfun.h:2099:70: note:   mismatched types 'const std::complex<_Tp>' and 'double'
 2099 |             ce1 = -el - std::log(-z) + z*ce1 - copysign(pi, z.imag())*std::complex<T>(0.0, 1.0);
      |                                                ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
/opt/local/include/gcc14/c++/complex:418:5: note: candidate: 'template<class _Tp> std::complex<_Tp> std::operator*(const _Tp&, const complex<_Tp>&)'
  418 |     operator*(const _Tp& __x, const complex<_Tp>& __y)
      |     ^~~~~~~~
/opt/local/include/gcc14/c++/complex:418:5: note:   template argument deduction/substitution failed:
../scipy/special/special/specfun/specfun.h:2099:70: note:   deduced conflicting types for parameter '_Tp' ('double' and 'float')
 2099 |             ce1 = -el - std::log(-z) + z*ce1 - copysign(pi, z.imag())*std::complex<T>(0.0, 1.0);
      |                                                ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
36-50% sudo   /opt/local/bin/g++-mp-14 -Iscipy/special/_special_ufuncs.cpython-311-darwin.so.p -Iscipy/special -I../scipy/special -Iscipy/_lib -I../scipy/_lib -I../scipy/_build_utils/src -I../../../../../../../../Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-packages/numpy/core/include -I/opt/local/Library/Frameworks/Python.framework/Versions/3.11/include/python3.11 -fvisibility=hidden -fvisibility-inlines-hidden -fdiagnostics-color=always -DNDEBUG -Wall -Winvalid-pch -std=gnu++17 -O3 -D_GLIBCXX_USE_CXX11_ABI=0 -isysroot/ -DSP_SPECFUN_ERROR -DNPY_NO_DEPRECATED_API=NPY_1_9_API_VERSION -MD -MQ scipy/special/_special_ufuncs.cpython-311-darwin.so.p/_special_ufuncs.cpp.o -MF scipy/special/_special_ufuncs.cpython-311-darwin.so.p/_special_ufuncs.cpp.o.d -o scipy/special/_special_ufuncs.cpython-311-darwin.so.p/_special_ufuncs.cpp.o -c ../scipy/special/_special_ufuncs.cpp

36-50%

Since spicy port uses legacysupport PG, it gets passed via environment, and that breaks the build here.

[barracuda156]

Just in case, defining __MP_LEGACY_SUPPORT_CXX11_CMATH__ to 0 or 1 (via MacportsLegacySupport.h) does not change the error.