Re: Barrier re-evaluation issue with GNAT 4.3.2

["Jeffrey R. Carter" <spam.jrcarter.not@spam.acm.org>]

Reto Buerki wrote:
> 
> Update: we just noticed that the warning actually *does* show up but we
> missed it in the previous build.
> 
> I also think the warning is irrelevant. It seems that the compiler is
> not smart enough to figure out that the Signal() entry is always open.

An entry call is always potentially blocking, regardless of its barrier; see ARM 
9.5.1. Technically, this code contains a bounded error. Since the potentially 
blocking operation was detected, your program should raise Program_Error; GNAT 
pretends that it hasn't detected that the operation is potentially blocking and 
lets you get away with only a warning. Other compilers (and even other versions 
of GNAT) may actually raise Program_Error.

-- 
Jeff Carter
"Strange women lying in ponds distributing swords
is no basis for a system of government."
Monty Python & the Holy Grail
66