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From: Thiago Adams <thiago.adams@gmail.com>
Newsgroups: comp.lang.c
Subject: What is your opinion about init_malloc?
Date: Fri, 14 Mar 2025 11:24:07 -0300
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What is your opinion about init_malloc?
One problem it solves it to initialise a const objects on heap.

#include <stdlib.h>
#include <string.h>
#include <stdio.h>

void * init_malloc(size_t size, void * src)
{
   void * p = malloc(size);
   if (p) {
      memcpy(p, src, size );
   }
   return p;
}

#define ALLOC(OBJ) ((typeof(OBJ)*) init_malloc(sizeof(OBJ), &(OBJ)))

////////// SAMPLE  //////////

struct Mail {
     const int id;
};

int main () {
     struct Mail* p0 = ALLOC((struct Mail){.id= 1});

     struct Mail* p1 = init_malloc(sizeof *p1, &(struct Mail){.id= 1});

     auto         p2 = ALLOC((struct Mail){.id= 1});

}

(I also posted on reddit)