Include `<cstdint>` in one place, remove custom typedefs

Originating from
[this SO issue](https://stackoverflow.com/questions/65901014/how-to-solve-this-all-error-2-in-this-case),
some win32 compilers define `__int32` as a `long`, but MinGW defines
`std::int32_t` as an `int`, leading to a type conflict.

To avoid this, we remove the custom `typedef` definitions for win32.  The
Tensor module requires C++11 anyways, so we are guaranteed to have
included `<cstdint>` already in `Eigen/Core`.

Also re-arranged the headers to only include `<cstdint>` in one place to
avoid this type of error again.

1 files changed, 35 insertions, 35 deletions

diff --git a/Eigen/src/Core/util/Meta.h b/Eigen/src/Core/util/Meta.h
index 64938d98d..ab1bc01da 100755
--- a/Eigen/src/Core/util/Meta.h
+++ b/Eigen/src/Core/util/Meta.h
@@ -25,8 +25,40 @@
 
 #endif
 
-#if EIGEN_COMP_ICC>=1600 &&  __cplusplus >= 201103L
+// Recent versions of ICC require <cstdint> for pointer types below.
+#define EIGEN_ICC_NEEDS_CSTDINT (EIGEN_COMP_ICC>=1600 && EIGEN_COMP_CXXVER >= 11)
+
+// Define portable (u)int{32,64} types
+#if EIGEN_HAS_CXX11 || EIGEN_ICC_NEEDS_CSTDINT
 #include <cstdint>
+namespace Eigen {
+namespace numext {
+typedef std::uint8_t  uint8_t;
+typedef std::int8_t   int8_t;
+typedef std::uint16_t uint16_t;
+typedef std::int16_t  int16_t;
+typedef std::uint32_t uint32_t;
+typedef std::int32_t  int32_t;
+typedef std::uint64_t uint64_t;
+typedef std::int64_t  int64_t;
+}
+}
+#else
+// Without c++11, all compilers able to compile Eigen also
+// provide the C99 stdint.h header file.
+#include <stdint.h>
+namespace Eigen {
+namespace numext {
+typedef ::uint8_t  uint8_t;
+typedef ::int8_t   int8_t;
+typedef ::uint16_t uint16_t;
+typedef ::int16_t  int16_t;
+typedef ::uint32_t uint32_t;
+typedef ::int32_t  int32_t;
+typedef ::uint64_t uint64_t;
+typedef ::int64_t  int64_t;
+}
+}
 #endif
 
 namespace Eigen {
@@ -52,13 +84,14 @@ namespace internal {
 
 // Only recent versions of ICC complain about using ptrdiff_t to hold pointers,
 // and older versions do not provide *intptr_t types.
-#if EIGEN_COMP_ICC>=1600 &&  __cplusplus >= 201103L
+#if EIGEN_ICC_NEEDS_CSTDINT
 typedef std::intptr_t  IntPtr;
 typedef std::uintptr_t UIntPtr;
 #else
 typedef std::ptrdiff_t IntPtr;
 typedef std::size_t UIntPtr;
 #endif
+#undef EIGEN_ICC_NEEDS_CSTDINT
 
 struct true_type {  enum { value = 1 }; };
 struct false_type { enum { value = 0 }; };
@@ -688,37 +721,4 @@ bool not_equal_strict(const double& x,const double& y) { return std::not_equal_t
 
 } // end namespace Eigen
 
-// Define portable (u)int{32,64} types
-#if EIGEN_HAS_CXX11
-#include <cstdint>
-namespace Eigen {
-namespace numext {
-typedef std::uint8_t  uint8_t;
-typedef std::int8_t   int8_t;
-typedef std::uint16_t uint16_t;
-typedef std::int16_t  int16_t;
-typedef std::uint32_t uint32_t;
-typedef std::int32_t  int32_t;
-typedef std::uint64_t uint64_t;
-typedef std::int64_t  int64_t;
-}
-}
-#else
-// Without c++11, all compilers able to compile Eigen also
-// provides the C99 stdint.h header file.
-#include <stdint.h>
-namespace Eigen {
-namespace numext {
-typedef ::uint8_t  uint8_t;
-typedef ::int8_t   int8_t;
-typedef ::uint16_t uint16_t;
-typedef ::int16_t  int16_t;
-typedef ::uint32_t uint32_t;
-typedef ::int32_t  int32_t;
-typedef ::uint64_t uint64_t;
-typedef ::int64_t  int64_t;
-}
-}
-#endif
-
 #endif // EIGEN_META_H