[PATCH] testsuite: C++14 vs. C++17 struct-layout-1.exp testing with ALT_CXX_UNDER_TEST [PR94383]

[Jeff Law]

On Thu, 2020-04-23 at 21:08 +0200, Jakub Jelinek via Gcc-patches wrote:
> Hi!
> 
> On Tue, Apr 21, 2020 at 11:57:02AM +0200, Jakub Jelinek wrote:
> > I haven't added (yet) checks if the alternate compiler does support these
> > options (I think that can be done incrementally), so for now this testing is
> > done only if the alternate compiler is not used.
> 
> This patch does that, so now when testing against not too old compiler
> it can do the -std=c++14 vs. -std=c++17 testing also between under test and
> alt compilers.
> 
> Tested on x86_64-linux, without ALT_CXX_UNDER_TEST (all tests still used),
> with ALT_CXX_UNDER_TEST=g++ (all tests still used too), and after tweaking
> it to test -std=c++20 instead of -std=c++17 that my system g++ doesn't
> support, where it only used tests before *_32* and bootstrapped/regtested
> on powerpc64{,le}-linux, ok for trunk?
> 
> 2020-04-23  Jakub Jelinek  <jakub@redhat.com>
> 
> 	PR c++/94383
> 	* g++.dg/compat/struct-layout-1.exp: Use the -std=c++14 vs. -std=c++17
> 	ABI compatibility testing even with ALT_CXX_UNDER_TEST, as long as
> 	that compiler accepts -std=c++14 and -std=c++17 options.
OK
jeff
>