[Bug c++/114091] New: gcc/config/aarch64/aarch64.cc has code requiring c++14 instead of c++11, so g++14 bootsrap fails in my example context

[Bug c++/114091] New: gcc/config/aarch64/aarch64.cc has code requiring c++14 instead of c++11, so g++14 bootsrap fails in my example context

[markmigm at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114091

            Bug ID: 114091
           Summary: gcc/config/aarch64/aarch64.cc has code requiring c++14
                    instead of c++11, so g++14 bootsrap fails in my
                    example context
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: markmigm at gmail dot com
  Target Milestone: ---

[I'm not sure where gcc/config/aarch64/aarch64.cc fits in the
component alternatives. Feel free to correct that if I got it
wrong.] 

gcc bootstrap is based on c++11, which predates the constructors for pair
being constexpr. The gcc/config/aarch64/aarch64.cc specific code can fail
because of using pair constructors where constant expressions are required:

/wrkdirs/usr/ports/lang/gcc14-devel/work/gcc-14-20240114/gcc/config/aarch64/aarch64.cc:13095:50:
error: constexpr variable 'tiles' must be initialized by a constant expression
static constexpr std::pair<unsigned int, char> tiles[] = {
^ ~
/wrkdirs/usr/ports/lang/gcc14-devel/work/gcc-14-20240114/gcc/config/aarch64/aarch64.cc:13096:5:
note: non-constexpr constructor 'pair<int, char, nullptr>' cannot be used in a
constant expression
{ 0xff, 'b' },
^

This stops the bootstrap in the example context.

This is detected when clang is doing the bootstrapping on FreeBSD.
For reference:

c++ -std=c++11  -fPIC -c   -g -DIN_GCC   -fno-strict-aliasing -fno-exceptions
-fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing -Wwrite-strings
-Wcast-qual -Wno-format -Wmissing-format-attribute -Wconditionally-supported
-Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros
-Wno-overlength-strings -fno-common  -DHAVE_CONFIG_H -fPIC -I. -I.
-I/wrkdirs/usr/ports/lang/gcc14-devel/work/gcc-14-20240114/gcc
-I/wrkdirs/usr/ports/lang/gcc14-devel/work/gcc-14-20240114/gcc/.
-I/wrkdirs/usr/ports/lang/gcc14-devel/work/gcc-14-20240114/gcc/../include 
-I/wrkdirs/usr/ports/lang/gcc14-devel/work/gcc-14-20240114/gcc/../libcpp/include
-I/wrkdirs/usr/ports/lang/gcc14-devel/work/gcc-14-20240114/gcc/../libcody
-I/usr/local/include 
-I/wrkdirs/usr/ports/lang/gcc14-devel/work/gcc-14-20240114/gcc/../libdecnumber
-I/wrkdirs/usr/ports/lang/gcc14-devel/work/gcc-14-20240114/gcc/../libdecnumber/bid
-I../libdecnumber
-I/wrkdirs/usr/ports/lang/gcc14-devel/work/gcc-14-20240114/gcc/../libbacktrace 
-DLIBICONV_PLUG -o aarch64.o -MT aarch64.o -MMD -MP -MF ./.deps/aarch64.TPo
/wrkdirs/usr/ports/lang/gcc14-devel/work/gcc-14-20240114/gcc/config/aarch64/aarch64.cc

where clang used its libc++ (its a FreeBSD context):

/usr/include/c++/v1/__utility/pair.h:225:5: note: declared here
  225 |     pair(_U1&& __u1, _U2&& __u2)
      |     ^

having -std=c++11 on the command line. That results in lack of
constexpr status in libc++ .

It would appear that until gcc bootstrap intends on being based on
c++14 (or later) that the gcc/config/aarch64/aarch64.cc code
reported is presuming a post-c++11 context when it should not be.

[Bug target/114091] gcc/config/aarch64/aarch64.cc has code requiring c++14 instead of c++11, so g++14 bootsrap fails in my example context

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114091

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |DUPLICATE

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
This has already been fixed, over 2 weeks ago.

>20240114

You are using a GCC 14 snapshot from a month ago even. Please try a newer
snapshot before reporting a bug next time.

*** This bug has been marked as a duplicate of bug 113763 ***

[Bug target/114091] gcc/config/aarch64/aarch64.cc has code requiring c++14 instead of c++11, so g++14 bootsrap fails in my example context

[markmigm at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114091

--- Comment #2 from Mark Millard <markmigm at gmail dot com> ---
(In reply to Andrew Pinski from comment #1)
> This has already been fixed, over 2 weeks ago.
> 
> >20240114
> 
> You are using a GCC 14 snapshot from a month ago even. Please try a newer
> snapshot before reporting a bug next time.
> 
> *** This bug has been marked as a duplicate of bug 113763 ***

Sorry. I was building a FreeBSD port and I'm not a port maintainer, much
less one for FreeBSD's lang/gcc14-devel .

I've sent the port maintainer a copy of your reply. Thanks.