default all fields in all ctors

include/pybind11/common.h

@@ -203,15 +203,15 @@ enum class return_value_policy : uint8_t {
 
 /// Information record describing a Python buffer object
 struct buffer_info {
-    void *ptr;                   // Pointer to the underlying storage
-    size_t itemsize;             // Size of individual items in bytes
-    size_t size;                 // Total number of entries
+    void *ptr = nullptr;         // Pointer to the underlying storage
+    size_t itemsize = 0;         // Size of individual items in bytes
+    size_t size = 0;             // Total number of entries
     std::string format;          // For homogeneous buffers, this should be set to format_descriptor<T>::format()
-    size_t ndim;                 // Number of dimensions
+    size_t ndim = 0;             // Number of dimensions
     std::vector<size_t> shape;   // Shape of the tensor (1 entry per dimension)
     std::vector<size_t> strides; // Number of entries between adjacent entries (for each per dimension)
 
-    buffer_info() : ptr(nullptr), view(nullptr) {}
+    buffer_info(){}
 
     buffer_info(void *ptr, size_t itemsize, const std::string &format, size_t ndim,
                 const std::vector<size_t> &shape, const std::vector<size_t> &strides)