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Date: Wed, 29 Jun 2011 08:06:00 -0000
Message-ID: <BANLkTi=Os1y_XFJrjX1T10tU6f5YSXKDsA@mail.gmail.com>
Subject: Re: [patch, fortran] Always return malloc(1) for empty arrays in the library
From: Janne Blomqvist <blomqvist.janne@gmail.com>
To: Thomas Koenig <tkoenig@netcologne.de>
Cc: "fortran@gcc.gnu.org" <fortran@gcc.gnu.org>, gcc-patches <gcc-patches@gcc.gnu.org>
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On Wed, Jun 29, 2011 at 00:50, Thomas Koenig <tkoenig@netcologne.de> wrote:
> Hello world,
>
> looking at PR 49479 and other functions in the library made me realize
> there are lots of places where we don't malloc one byte for empty
> arrays.

I'd prefer to add the zero check to runtime/memory.c
(internal_malloc_size), i.e. change

if (size == 0)
  return NULL;

to

if (size == 0)
  size = 1;

Or perhaps even better would be to add that check to get_mem() instead
(as a side effect making internal_malloc_size redundant), thus
matching how memory allocation works in the frontend? Looking at
get_mem() we actually have a small bug here; if size == 0 and malloc
happens to return NULL we treat it as an error.

-- 
Janne Blomqvist