I can not use importC, I need it to be work in D code.

typedef struct {
  uint32_t mask_limit;   // Limit enum value that can be tested with mask.
  uint32_t value_count;  // Number of values after the bitfield.
  uint32_t data[];       // Bitmask + enumerated values follow.
} upb_MiniTable_Enum;

I am not sure how to define the __gshared const upb_MiniTable_Enum object for this struct.

On Tuesday, 13 September 2022 at 06:04:49 UTC, test123 wrote:

typedef struct {
  uint32_t mask_limit;   // Limit enum value that can be tested with mask.
  uint32_t value_count;  // Number of values after the bitfield.
  uint32_t data[];       // Bitmask + enumerated values follow.
} upb_MiniTable_Enum;

struct mystruct {
  uint32_t mask_limit;   // Limit enum value that can be tested with mask.
  uint32_t value_count;  // Number of values after the bitfield.
  uint32_t[] data;       // Bitmask + enumerated values follow.
} __gshared mystruct upb_MiniTable_Enum;

On Tuesday, 13 September 2022 at 07:31:50 UTC, Marvin wrote:

typedef struct {
  uint32_t mask_limit;   // Limit enum value that can be tested with mask.
  uint32_t value_count;  // Number of values after the bitfield.
  uint32_t data[];       // Bitmask + enumerated values follow.
} upb_MiniTable_Enum;

struct mystruct {
  uint32_t mask_limit;   // Limit enum value that can be tested with mask.
  uint32_t value_count;  // Number of values after the bitfield.
  uint32_t[] data;       // Bitmask + enumerated values follow.
} __gshared mystruct upb_MiniTable_Enum;

This will not work since the C have no array like D.

On Tuesday, 13 September 2022 at 09:43:46 UTC, test123 wrote:

You can use a 0-size static array:

struct mystruct {
	uint32_t mask_limit;   // Limit enum value that can be tested with mask.
	uint32_t value_count;  // Number of values after the bitfield.
	uint32_t[0] data;      // Bitmask + enumerated values follow.
}

Then you have to index with mystructVar.data.ptr[i] to avoid bounds checking.

On Tuesday, 13 September 2022 at 09:57:38 UTC, Dennis wrote:

struct mystruct {
	uint32_t mask_limit;   // Limit enum value that can be tested with mask.
	uint32_t value_count;  // Number of values after the bitfield.
	uint32_t[0] data;      // Bitmask + enumerated values follow.
}

Thanks, this look nice.

What I need is init the const object at CTFE.

I try this way:

    struct validate_KnownRegex_enum_init_type { const upb_MiniTable_Enum header; uint[2] data; }
    __gshared const validate_KnownRegex_enum_init_type validate_KnownRegex_enum_init = { {64, 2}, [7, 0] };

The problem is I can not assign it into one array (give error):

    __gshared const test = cast(upb_MiniTable_Enum*) &validate_KnownRegex_enum_init;
    __gshared const __enums_layout = [
        test,
    ];

This will also not work:

    __gshared const upb_MiniTable_Enum*[1] __enums_layout = [
        &validate_KnownRegex_enum_init.header,
    ];

Is there a way to init the __gshared fixed length upb_MiniTable_Enum array ?

On Tuesday, 13 September 2022 at 10:45:03 UTC, test123 wrote:

2 type error I think it cloud be compiler bugs.

1): expression &validate_KnownRegex_enum_init_type(64u, 2u, [7u, 0u], ).header is not a constant

    union validate_KnownRegex_enum_init_type { struct {uint a, b; uint[2] data;} upb_MiniTable_Enum header; }
    __gshared const validate_KnownRegex_enum_init_type validate_KnownRegex_enum_init = { 64, 2, [7, 0] };
    __gshared const upb_MiniTable_Enum*[1] __enums_layout = [
        &validate_KnownRegex_enum_init.header,
    ];

2:) Error: reinterpreting cast from const(validate_KnownRegex_enum_init_type)toconst(upb_MiniTable_Enum) is not supported in CTFE

    struct validate_KnownRegex_enum_init_type { uint a, b; uint[2] data;}
    __gshared const validate_KnownRegex_enum_init_type validate_KnownRegex_enum_init = { 64, 2, [7, 0] };
    __gshared const upb_MiniTable_Enum*[1] __enums_layout = [
        cast(const upb_MiniTable_Enum*) &validate_KnownRegex_enum_init,
    ];

On Tuesday, 13 September 2022 at 10:45:03 UTC, test123 wrote:

I don't think so. You could leave your array typed as validate_KnownRegex_enum_init_type and access it through a function that casts it to upb_MiniTable_Enum.

Side node, you can use immutable instead of __gshared const, it amounts to the same for global variables.

On Tuesday, 13 September 2022 at 10:59:36 UTC, Dennis wrote:

I can not do this. because fixed sized array upb_MiniTable_Enum[] is passed into other const object. and upb_MiniTable_Enum can include a lot diff types. (for example mixed diff size upb_MiniTable_Enum)

On Tuesday, 13 September 2022 at 10:59:36 UTC, Dennis wrote:

replace with immutable get this error:

static variable `__enums_layout` cannot be read at compile time

On Tuesday, 13 September 2022 at 10:59:36 UTC, Dennis wrote:

because __enums_layout.ptr need to be part of other object, and this const ptr cloud be included in multi objects.