Boost C++ Libraries: Ticket #7242: GCC 4.8 warns unused local typedef

larsbj@… — Fri, 24 Aug 2012 22:40:05 GMT

Have you actually tried to use __attribute__((unused)) to suppress these warnings? I can not make it work.

Sat, 25 Aug 2012 05:17:57 GMT

I tried followings, and it works for me.

#include <boot/static_assert.hpp>
int main()
{
	BOOST_STATIC_ASSERT(true) __attribute__((unused));
}

However, in some cases seems doesn't work and I think it's GCC defect. I'll try to narrow down the cause and report it to GCC bugzilla.

Sat, 29 Sep 2012 01:16:22 GMT

The GCC defects fixed in trunk; http://gcc.gnu.org/PR54372 . The solution works well, now.

status changed; resolution set

John Maddock — Thu, 14 Feb 2013 18:31:35 GMT

status new → closed
resolution → fixed

(In [82886]) Use variadic macros in static assert to make use easier. Add warning suppression for GCC. Minor doc fix. Fixes #5810. Fixes #7242. Fixes #7966.

laurent.rineau__boost_trac@… — Thu, 14 Mar 2013 13:32:32 GMT

Will that patch be included in version 1.54?

anonymous — Tue, 19 Mar 2013 18:10:31 GMT

Should be yes.

anonymous — Wed, 15 Jul 2015 09:08:21 GMT

I see the same warning with clang-3.6.1.

The GCC syntax:

__attribute__((unused))

is accepted by clang, at least since clang-3.4. I suggest to adapt the following lines, of boost/static_assert.hpp so that clang>=3.4 is also taken into account:

#if defined(__GNUC__) && ((__GNUC__ > 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)))
#  define BOOST_STATIC_ASSERT_UNUSED_ATTRIBUTE __attribute__((unused))
#else
#  define BOOST_STATIC_ASSERT_UNUSED_ATTRIBUTE
#endif

Should I open a new ticket?