type/function redefinition when same tuple/list type appear in both typedef and funcdef

[7sDream]

// ./wit/issue.wit
default world issue {
    union union-list-u8 {
        list<u8>,
    }

    record record-tuple-u8 {
        field: tuple<u8>,
    }
    
    variant variant-list-tuple-bool {
        field(list<tuple<bool>>),
    }

    import func-using-list-u8-in-args: func(body: list<u8>) -> ()
    export func-using-tuple-u8-in-return: func() -> tuple<u8>
    export func-using-list-tuple-bool-in-return: func() -> list<tuple<bool>>
}

just a simple WIT file, and using wit-bindgen c --out-dir=gen ./wit, it generates:

Generated .h file

// Generated by `wit-bindgen` 0.4.0. DO NOT EDIT!
#ifndef __BINDINGS_ISSUE_H
#define __BINDINGS_ISSUE_H
#ifdef __cplusplus
extern "C" {
#endif

#include <stdlib.h>
#include <stdint.h>
#include <stdbool.h>

typedef struct {
  bool f0;
} issue_tuple1_bool_t;

typedef struct {
  issue_tuple1_bool_t *ptr;
  size_t len;
} issue_list_tuple1_bool_t;

typedef struct {
  uint8_t tag;
  union {
    issue_list_tuple1_bool_t field;
  } val;
} issue_variant_list_tuple_bool_t;

#define ISSUE_VARIANT_LIST_TUPLE_BOOL_FIELD 0

typedef struct {
  uint8_t *ptr;
  size_t len;
} issue_list_u8_t;

typedef struct {
  uint8_t tag;
  union {
    issue_list_u8_t f0;
  } val;
} issue_union_list_u8_t;

typedef struct {
  uint8_t f0;
} issue_tuple1_u8_t;

typedef struct {
  issue_tuple1_u8_t field;
} issue_record_tuple_u8_t;

typedef struct {
  uint8_t *ptr;
  size_t len;
} issue_list_u8_t;

typedef struct {
  bool f0;
} issue_tuple1_bool_t;

typedef struct {
  issue_tuple1_bool_t *ptr;
  size_t len;
} issue_list_tuple1_bool_t;

typedef struct {
  uint8_t f0;
} issue_tuple1_u8_t;

// Imported Functions from `issue`
void issue_func_using_list_u8_in_args(issue_list_u8_t *body);

// Exported Functions from `issue`
void issue_func_using_tuple_u8_in_return(issue_tuple1_u8_t *ret);
void issue_func_using_list_tuple_bool_in_return(issue_list_tuple1_bool_t *ret);

// Helper Functions

void issue_list_tuple1_bool_free(issue_list_tuple1_bool_t *ptr);
void issue_variant_list_tuple_bool_free(issue_variant_list_tuple_bool_t *ptr);
void issue_list_u8_free(issue_list_u8_t *ptr);
void issue_union_list_u8_free(issue_union_list_u8_t *ptr);
void issue_list_u8_free(issue_list_u8_t *ptr);
void issue_list_tuple1_bool_free(issue_list_tuple1_bool_t *ptr);

#ifdef __cplusplus
}
#endif
#endif

You can see it defines thoose type/function twice:

• type issue_list_u8_t and function issue_list_u8_free
• type issue_tuple1_bool_t
• type issue_list_tuple1_bool_t and function issue_list_tuple1_bool_free
• type issue_tuple1_u8_t

Then it makes compiling fail.

I meet this issue when trying the tinygo generator, and the golang wrap type is defined twice too, so it seems to be a common behavior, is this by design?

And I tried type alias, this can fix redefinition issue, so I should alias each complex type instead of using them directly?

[alexcrichton]

Thanks for the report! I've started a fix for this at #545