Re: [PATCH 1/2] Add gcc/make-unique.h

[Pedro Alves <pedro@palves.net>]

On 2022-07-12 1:25 a.m., David Malcolm via Gcc-patches wrote:

> I tried adding it to gcc/system.h, but anything that uses it needs to
> have std::unique_ptr declared, which meant forcibly including <memory>
> from gcc/system.h

Did you consider making gcc/system.h include gcc/make-unique.h itself 
if INCLUDE_MEMORY is defined?  Something like:

 #ifdef INCLUDE_MEMORY
 # include <memory>
+ #include "make-unique.h"
 #endif

This is because std::make_unique is defined in <memory> in C++14.  This would
mean fewer changes once GCC requires C++14 (or later) and this new header is eliminated.

> (in the root namespace, rather than std::, which saves a bit more typing).

It's less typing now, but it will be more churn once GCC requires C++14 (or later), at
which point you'll naturally want to get rid of the custom make_unique.  More churn
since make_unique -> std::make_unique may require re-indentation of arguments, etc.
For that reason, I would suggest instead to put the function (and any other straight
standard library backport) in a 3-letter namespace already, like, gcc::make_unique
or gnu::make_unique.  That way, when the time comes that GCC requires C++14,
the patch to replace gcc::make_unique won't have to worry about reindenting code,
it'll just replace gcc -> std.