ax_gcc_func_attribute
=====================

Synopsis
********

     AX_GCC_FUNC_ATTRIBUTE(ATTRIBUTE)

Description
***********

This macro checks if the compiler supports one of GCC's function attributes; many other compilers also provide function attributes with the same syntax. Compiler warnings are used to detect supported attributes as unsupported ones are ignored by default so quieting warnings when using this macro will yield false positives.

The ATTRIBUTE parameter holds the name of the attribute to be checked.

If ATTRIBUTE is supported define HAVE_FUNC_ATTRIBUTE_<ATTRIBUTE>.

The macro caches its result in the ax_cv_have_func_attribute_<attribute> variable.

The macro currently supports the following function attributes:

      alias
      aligned
      alloc_size
      always_inline
      artificial
      cold
      const
      constructor
      constructor_priority for constructor attribute with priority
      deprecated
      destructor
      dllexport
      dllimport
      error
      externally_visible
      fallthrough
      flatten
      format
      format_arg
      gnu_inline
      hot
      ifunc
      leaf
      malloc
      noclone
      noinline
      nonnull
      noreturn
      nothrow
      optimize
      pure
      sentinel
      sentinel_position
      unused
      used
      visibility
      warning
      warn_unused_result
      weak
      weakref

Unsupported function attributes will be tested with a prototype returning an int and not accepting any arguments and the result of the check might be wrong or meaningless so use with care.

Source Code
***********

Download the latest version of ax_gcc_func_attribute.m4 (http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=blob_plain;f=m4/ax_gcc_func_attribute.m4) or browse the macro's revision history (http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=history;f=m4/ax_gcc_func_attribute.m4).

License
*******

Copyright © 2013 Gabriele Svelto gabriele.svelto@gmail.com

Copying and distribution of this file, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved.  This file is offered as-is, without any warranty.