numpy: More faithfully reflect npy_common.h aliases

Author: EricCousineau-TRI

include/pybind11/numpy.h

@@ -145,14 +145,17 @@ struct npy_api {
         NPY_UINT8_ = NPY_UBYTE_,
         NPY_INT16_ = NPY_SHORT_,
         NPY_UINT16_ = NPY_USHORT_,
-        NPY_INT32_ = platform_lookup<std::int32_t, short, int, long>({{
-            NPY_SHORT_, NPY_INT_, NPY_LONG_}}),
-        NPY_UINT32_ = platform_lookup<std::uint32_t, unsigned short, unsigned int, unsigned long>({{
-            NPY_USHORT_, NPY_UINT_, NPY_ULONG_}}),
-        NPY_INT64_ = platform_lookup<std::int64_t, int, long, long long>({{
-            NPY_INT_, NPY_LONG_, NPY_LONGLONG_}}),
-        NPY_UINT64_ = platform_lookup<std::uint64_t, unsigned int, unsigned long, unsigned long long>({{
-            NPY_UINT_, NPY_ULONG_, NPY_ULONGLONG_}}),
+        // `npy_common.h` defines the integer aliases. In order, it checks:
+        // NPY_BITSOF_LONG, NPY_BITSOF_LONGLONG, NPY_BITSOF_INT, NPY_BITSOF_SHORT, NPY_BITSOF_CHAR
+        // and assigns the alias to the first matching size, so we should check in this order.
+        NPY_INT32_ = platform_lookup<std::int32_t, long, int, short>({{
+            NPY_LONG_, NPY_INT_, NPY_SHORT_}}),
+        NPY_UINT32_ = platform_lookup<std::uint32_t, unsigned long, unsigned int, unsigned short>({{
+            NPY_ULONG_, NPY_UINT_, NPY_USHORT_}}),
+        NPY_INT64_ = platform_lookup<std::int64_t, long, long long, int>({{
+            NPY_LONG_, NPY_LONGLONG_, NPY_INT_}}),
+        NPY_UINT64_ = platform_lookup<std::uint64_t, unsigned long, unsigned long long, unsigned int>({{
+            NPY_ULONG_, NPY_ULONGLONG_, NPY_UINT_}}),
     };
 
     typedef struct {