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Documentation request: allocation of bigarrays in C
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Date: -- (:)
From: sayan@c...
Subject: Documentation request: allocation of bigarrays in C
Hi,

Please add the following fact to the Bigarray module documentation (I 
had to look at the c source header) and/or correct it as necessary :

A pointer allocated from C using malloc is not freed by the OCaml 
garbage collector. If you want to be GC-friendly, use the bigarray 
allocation macros with a NULL pointer to allocate memory then get a 
pointer to the data array.

Example:

Instead of
float* carray;
carray = malloc(sizeof(float)*size);
CAMLlocal1(res);
res = alloc_bigarray_dims(BIGARRAY_FLOAT32 | 
BIGARRAY_C_LAYOUT,1,carray,size);
CAMLreturn(res);

Write
CAMLlocal1(res);
res = alloc_bigarray_dims(BIGARRAY_FLOAT32 | BIGARRAY_C_LAYOUT,1,NULL,size);
float* carray = Data_bigarray_val(res);
CAMLreturn(res);

Regards,

-- 
Li-Thiao-Té Sébastien