On Wed, Feb 28, 2018 at 5:47 PM, Martin Sebor <mse...@gmail.com> wrote:
> Attached is a patch for the failure to merge a subset of attributes
> specified on redeclarations of a function template with those of
> the first declaration (const, malloc, pure, noinline, noreturn,
> and nothrow). This was uncovered this morning while debugging
> failures in tests I added just yesterday and although it's not
> a regression I figured since I introduced the test failures and
> the fix appears easy it might as well be taken care of now.
>
> The test I added for this exposed a subtle bug in -Wreturn-type
> where the warning triggers on a function template instantiated
> on a noreturn function even though the middle end successfully
> eliminates statements after the noreturn call. This is not
> a regression either so to avoid mission creep I just xfailed
> the test and opened bug 84621 to remind us to fix it in
> the future.
OK. Incidentally, looking over duplicate_decls again, I noticed:
/* [temp.expl.spec/14] We don't inline explicit
specialization
just because the primary template says so. */
if (merge_attr)
{
/* But still keep DECL_DISREGARD_INLINE_LIMITS in sync
with
the always_inline attribute. */
if (DECL_DISREGARD_INLINE_LIMITS (olddecl)
&& !DECL_DISREGARD_INLINE_LIMITS (newdecl))
{
if (DECL_DECLARED_INLINE_P (newdecl))
DECL_DISREGARD_INLINE_LIMITS (newdecl) = true;
else
DECL_ATTRIBUTES (newdecl)
= remove_attribute ("always_inline",
DECL_ATTRIBUTES (newdecl));
}
}
else
{
DECL_DECLARED_INLINE_P (olddecl)
= DECL_DECLARED_INLINE_P (newdecl);
DECL_DISREGARD_INLINE_LIMITS (olddecl)
= DECL_DISREGARD_INLINE_LIMITS (newdecl);
DECL_UNINLINABLE (olddecl) = DECL_UNINLINABLE (newdecl);
}
The upper block here seems like dead code; here we're dealing with an
explicit specialization, so merge_attr should always be false. Let's
drop the if block.
Jason
