Error parsing input for const deceleration in ANTLR CPP Grammar

Question

I am using the below ANTLR grammar for parsing my code.

https://github.com/antlr/grammars-v4/tree/master/cpp

But I am getting a parsing error in the below part of my code

const GstTensorsInfo info_in = {
        .num_tensors = 1U,
        .info = {{ .name = NULL, .type = _NNS_UINT8, .dimension = { 1, 10, 1, 1}}},
      };

I am using the below input for the CPP parser:

TEST(tensor_filter_custom_easy, in_code_func_01)
    {
      int ret;
      const guint num_buffers = 10;
      TestOption option = { num_buffers, TEST_CUSTOM_EASY_ICF_01 };
      guint timeout_id;
    
      const GstTensorsInfo info_in = {
        .num_tensors = 1U,
        .info = {{ .name = NULL, .type = _NNS_UINT8, .dimension = { 1, 10, 1, 1}}},
      };
      
      ret = NNS_custom_easy_register ("safe_memcpy_10x10", cef_func_safe_memcpy,
          NULL, &info_in, &info_out);
      ASSERT_EQ(ret, 0);
    }

What modification is needed in parser/lexer to parse the input correctly? Any help on this is highly appreciated. Thanks in advance.

Answer 1

The designated initializer syntax (.num_tensors = 1U) was only added to C++ in C++20. The grammar you are trying to use is named "CPP14", which I suppose means that it is a C++14 grammar. In that case, it's not surprising that it doesn't accept the syntax.

You might be able to find something useful in a C grammar, since designated initializers have been part of C since C99.