bug: Default member initializer with value of zero parsed as pure virtual function

Did you check existing issues?

• I have read all the tree-sitter docs if it relates to using the parser
• I have searched the existing issues of tree-sitter-cpp

Tree-Sitter CLI Version, if relevant (output of tree-sitter --version)

No response

Describe the bug

A default member initialization is interpreted as a pure virtual clause when the value is zero. I'm unsure whether or not this is a fundamental ambiguity in C++ syntax.

Steps To Reproduce/Bad Parse Tree

The following code:

struct A {
  int x = 0;
};

parses to:

translation_unit [0, 0] - [4, 0]
  struct_specifier [0, 0] - [2, 1]
    name: type_identifier [0, 7] - [0, 8]
    body: field_declaration_list [0, 9] - [2, 1]
      function_definition [1, 2] - [1, 12]
        type: primitive_type [1, 2] - [1, 5]
        declarator: field_identifier [1, 6] - [1, 7]
        pure_virtual_clause [1, 8] - [1, 12]

i.e. the = 0 there is interpreted as x being a function that is pure virtual.

Expected Behavior/Parse Tree

A value other than zero seems to work as expected:

struct A {
  int x = 1;
};

gives:

translation_unit [0, 0] - [4, 0]
  struct_specifier [0, 0] - [2, 1]
    name: type_identifier [0, 7] - [0, 8]
    body: field_declaration_list [0, 9] - [2, 1]
      field_declaration [1, 2] - [1, 12]
        type: primitive_type [1, 2] - [1, 5]
        declarator: field_identifier [1, 6] - [1, 7]
        default_value: number_literal [1, 10] - [1, 11]

Repro

No response

No repository file or test is named. Start by reproducing the struct A { int x = 0; }; example and inspect the grammar entry points producing field_declaration and pure_virtual_clause; done means zero-valued default member initializers produce the same field structure as the value-1 example.