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42 lines
1.4 KiB
Plaintext
42 lines
1.4 KiB
Plaintext
# Check whether free (NULL) is supposed to work.
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# Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
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# This file is free software; the Free Software Foundation
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# gives unlimited permission to copy and/or distribute it,
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# with or without modifications, as long as this notice is preserved.
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# Written by Paul Eggert.
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# We can't test for free (NULL) even at runtime, since it might
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# happen to "work" for our test program, but not in general. So, be
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# conservative and use feature tests for relatively modern hosts,
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# where free (NULL) is known to work. This costs a bit of
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# performance on some older hosts, but we can fix that later if
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# needed.
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AC_DEFUN([gl_FUNC_FREE],
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[
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AC_CHECK_HEADERS_ONCE(unistd.h)
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AC_CACHE_CHECK([whether free (NULL) is known to work],
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[gl_cv_func_free],
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[AC_COMPILE_IFELSE(
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[AC_LANG_PROGRAM(
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[[@%:@include <unistd.h>]],
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[[@%:@if _POSIX_VERSION < 199009L && \
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(defined unix || defined _unix || defined _unix_ \
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|| defined __unix || defined __unix__)
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@%:@error "'free (NULL)' is not known to work"
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@%:@endif]])],
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[gl_cv_func_free=yes],
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[gl_cv_func_free=no])])
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if test $gl_cv_func_free = no; then
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AC_LIBOBJ(free)
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AC_DEFINE(free, rpl_free,
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[Define to rpl_free if the replacement function should be used.])
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fi
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])
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# Prerequisites of lib/free.c.
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AC_DEFUN([gl_PREREQ_FREE], [:])
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