Merge pull request #23521 from seiko2plus/cpp_2017

ENH: Raise C++ standard to C++17

2 files changed, 4 insertions, 42 deletions

diff --git a/numpy/core/setup.py b/numpy/core/setup.py
index 77561827a..680c2a5f6 100644
--- a/numpy/core/setup.py
+++ b/numpy/core/setup.py
@@ -405,7 +405,6 @@ def configuration(parent_package='',top_path=None):
                                            exec_mod_from_location)
     from numpy.distutils.system_info import (get_info, blas_opt_info,
                                              lapack_opt_info)
-    from numpy.distutils.ccompiler_opt import NPY_CXX_FLAGS
     from numpy.version import release as is_released
 
     config = Configuration('core', parent_package, top_path)
@@ -658,44 +657,6 @@ def configuration(parent_package='',top_path=None):
         # but we cannot use add_installed_pkg_config here either, so we only
         # update the substitution dictionary during npymath build
         config_cmd = config.get_config_cmd()
-        # Check that the toolchain works, to fail early if it doesn't
-        # (avoid late errors with MATHLIB which are confusing if the
-        # compiler does not work).
-        for lang, test_code, note in (
-            ('c', 'int main(void) { return 0;}', ''),
-            ('c++', (
-                    'int main(void)'
-                    '{ auto x = 0.0; return static_cast<int>(x); }'
-                ), (
-                    'note: A compiler with support for C++11 language '
-                    'features is required.'
-                )
-             ),
-        ):
-            is_cpp = lang == 'c++'
-            if is_cpp:
-                # this a workaround to get rid of invalid c++ flags
-                # without doing big changes to config.
-                # c tested first, compiler should be here
-                bk_c = config_cmd.compiler
-                config_cmd.compiler = bk_c.cxx_compiler()
-
-                # Check that Linux compiler actually support the default flags
-                if hasattr(config_cmd.compiler, 'compiler'):
-                    config_cmd.compiler.compiler.extend(NPY_CXX_FLAGS)
-                    config_cmd.compiler.compiler_so.extend(NPY_CXX_FLAGS)
-
-            st = config_cmd.try_link(test_code, lang=lang)
-            if not st:
-                # rerun the failing command in verbose mode
-                config_cmd.compiler.verbose = True
-                config_cmd.try_link(test_code, lang=lang)
-                raise RuntimeError(
-                    f"Broken toolchain: cannot link a simple {lang.upper()} "
-                    f"program. {note}"
-                )
-            if is_cpp:
-                config_cmd.compiler = bk_c
         mlibs = check_mathlib(config_cmd)
 
         posix_mlib = ' '.join(['-l%s' % l for l in mlibs])
@@ -1067,8 +1028,7 @@ def configuration(parent_package='',top_path=None):
                                 common_deps,
                          libraries=['npymath'],
                          extra_objects=svml_objs,
-                         extra_info=extra_info,
-                         extra_cxx_compile_args=NPY_CXX_FLAGS)
+                         extra_info=extra_info)
 
     #######################################################################
     #                        umath_tests module                           #
diff --git a/numpy/core/src/npymath/npy_math_private.h b/numpy/core/src/npymath/npy_math_private.h
index a474b3de3..20c94f98a 100644
--- a/numpy/core/src/npymath/npy_math_private.h
+++ b/numpy/core/src/npymath/npy_math_private.h
@@ -21,6 +21,7 @@
 #include <Python.h>
 #ifdef __cplusplus
 #include <cmath>
+#include <complex>
 using std::isgreater;
 using std::isless;
 #else
@@ -494,8 +495,9 @@ do {                                                            \
  * Microsoft C defines _MSC_VER
  * Intel compiler does not use MSVC complex types, but defines _MSC_VER by
  * default.
+ * since c++17 msvc is no longer support them.
  */
-#if defined(_MSC_VER) && !defined(__INTEL_COMPILER)
+#if !defined(__cplusplus) && defined(_MSC_VER) && !defined(__INTEL_COMPILER)
 typedef union {
         npy_cdouble npy_z;
         _Dcomplex c99_z;