typedef struct {
  const char *str;
  size_t      len : 30;
  bool        initial : 1;
  bool        final : 1;
} VTermStringFragment;

struct VTerm
{
  const VTermAllocatorFunctions *allocator;
  void *allocdata;

  int rows;
  int cols;

  struct {
    unsigned int utf8:1;
    unsigned int ctrl8bit:1;
  } mode;

  struct {
    enum VTermParserState {
      NORMAL,
      CSI_LEADER,
      CSI_ARGS,
      CSI_INTERMED,
      DCS_COMMAND,
      /* below here are the "string states" */
      OSC_COMMAND,
      OSC,
      DCS,
      APC,
      PM,
      SOS,
    } state;

    bool in_esc : 1;

    int intermedlen;
    char intermed[INTERMED_MAX];

    union {
      struct {
        int leaderlen;
        char leader[CSI_LEADER_MAX];

        int argi;
        long args[CSI_ARGS_MAX];
      } csi;
      struct {
        int command;
      } osc;
      struct {
        int commandlen;
        char command[CSI_LEADER_MAX];
      } dcs;
    } v;

    const VTermParserCallbacks *callbacks;
    void *cbdata;

    bool string_initial;
  } parser;

}

VTermStringFragment for mingw-x64 clang size is 24, for unix-64 is 16.

VTerm for mingw-x64 clang size is 144, fox unix-64 is 208.

VTerm for mingw-x86 clang size is 128.

and offsetoff also diff from unix.

how to translate this into D struct ?

Is this problem cause by clang has wrong layout?

On Monday, 16 May 2022 at 05:57:33 UTC, test123 wrote:

and VTermStringFragment for mingw-x86 size is 12.

On Monday, 16 May 2022 at 05:58:17 UTC, test123 wrote:

VTerm->parser for mingw-x64 clang size is 144, fox unix-64 is 208.

VTerm->parser for mingw-x86 clang size is 128.

On Monday, 16 May 2022 at 05:57:33 UTC, test123 wrote:

typedef struct {
  const char *str;
  size_t      len : 30;
  bool        initial : 1;
  bool        final : 1;
} VTermStringFragment;

[...]

Without fully scrutinizing your code I suspect the issues you see are caused by:

• alignment
• struct context pointer

see:

https://dlang.org/spec/attribute.html#align
and
https://dlang.org/spec/attribute.html#static

On Monday, 16 May 2022 at 07:29:39 UTC, Arjan wrote:

I know it is cause by alignment. my problem how to deal with diff alignment with diff platform. special when there is multi level nested struct.

There is no struct context pointer since I translate all nested struct and union into static.

struct work for linux with clang, but not for windows.

On Monday, 16 May 2022 at 12:51:01 UTC, test123 wrote:

Nesting does not make a difference in c/c++, it does however in D.

That is not shown in the code.

Its it not clear what you want to achieve, assuming you want these structs to be equal (binary compatible layout on systems with same endianness)

• enforce in C/C++ the alignment to byte/word/dword/qword alignment. This could be done with compiler #pragma pack or from C++/11 alignas or c/11 _Alignas (see https://en.cppreference.com/w/cpp/language/alignas)
  to make sure the padding is the same.
• do not use bitfields since the packing of adjacent fields is implementation (compiler) dependent. (most probably the cause for diff in size 16 <==> 24 as you observed) see https://en.cppreference.com/w/cpp/language/bit_field
• make sure the type's used in the struct are architecture independent, size of int in c/c++ is dependent on target arch x86=> 32bits x86_64 64bits. Its fixed in D.
• make sure the size_t is the same type and size for all platforms
• use static struct in D
• use the correct corresponding types https://dlang.org/spec/type.html in D or use core.stdc.stdint type aliases

On Monday, 16 May 2022 at 15:28:42 UTC, Arjan wrote:

I can not change c struct since I don't own the project but need deal with it.

All subtype size is matched that is why posix test work (and also check offsetof is matched).

The problem is even all subtype size is same, but not all platform has same memory layout.

On Tuesday, 17 May 2022 at 09:40:40 UTC, test123 wrote:

Maybe extern(Windows) can do something?
Also, maybe useful : https://forum.dlang.org/post/ktntbwppqgbbajpbmrcf@forum.dlang.org

On Tuesday, 17 May 2022 at 09:40:40 UTC, test123 wrote:

Do you know how this 'c' part is build? Which compiler and compiler flags?
Than you should be able to 'deduce' the alignment used an possibly the packing of bitfields.

When you know these things you are able to craft the D equivalent.

Another option is just to figure out the layout at runtime using a on purpose filled struct from 'c' with 'marker patterns' in the struct fields.

On Tuesday, 17 May 2022 at 10:05:21 UTC, Tejas wrote:

It is extern(C).

On Tuesday, 17 May 2022 at 19:52:23 UTC, Arjan wrote:

Clang with makefile.

no alignment is settings from C source file.

sound like a solution, but not how to do this.