malloc/dynarray-skeleton.c problems on MacOS 10.13.6 and 10.15.7

[arnold]

Hi Paul & Jim,

Please see the report below from Nelson Beebe, attempting to build
https://www.skeeve.com/gawk/gawk-5.1.1a.tar.gz on recent MacOS.
This a test release, working towards a real release.

Can you pleae work directly with Nelson in terms of patches etc and
then let me know when Gnulib is updated?

Much thanks,

Arnold

> Date: Thu, 6 May 2021 15:15:08 -0600
> From: "Nelson H. F. Beebe" <beebe@math.utah.edu>
> Subject: Re: Release spiral start
>
> I got successful builds and installations of gawk-5.1.1a on several
> systems, include CentOS 5/6/7/8, Ubuntu 20.04, Debian 7 (MIPS32),
> Oracle 8, Red Hat 8, and Solaris 10, but build attempts on macOS
> 10.13.6 and 10.15.7 with both Apple's /usr/bin/cc (really clang 12)
> and /usr/bin/gcc (clang 12 masquerading as gcc), plus on macOS
> 10.13.6, gcc-{4,5,6,7,8,9,10,11,12}, have all failed.
>
> The killer code is the several instances of __nonnull ((1)) in
> support/malloc/dynarray-skeleton.c.  They produce a cascade of errors
> that start like this:
>
>       /usr/bin/gcc -DGAWK -DHAVE_CONFIG_H -I"./.." -I. -I..    \
>                      -g -O2 -DNDEBUG -g -O2 -DNDEBUG -MT regex.o \
>                      -MD -MP -MF $depbase.Tpo -c -o regex.o      \
>                      regex.c &&                                  \
>       mv -f $depbase.Tpo $depbase.Po
> In file included from regex.c:74:
> In file included from ./regexec.c:1368:
> ./malloc/dynarray-skeleton.c:195:13: error: expected ')'
> __nonnull ((1))
>             ^
> ./malloc/dynarray-skeleton.c:195:12: note: to match this '('
> __nonnull ((1))
>            ^
> ./malloc/dynarray-skeleton.c:195:13: warning: type specifier missing, 
> defaults to 'int' [-Wimplicit-int]
> __nonnull ((1))
>             ^
> ./malloc/dynarray-skeleton.c:195:1: warning: type specifier missing, defaults 
> to 'int' [-Wimplicit-int]
> __nonnull ((1))
>
> ... many more ...
>
> -------------------------------------------------------------------------------
> - Nelson H. F. Beebe                    Tel: +1 801 581 5254                  
> -
> - University of Utah                    FAX: +1 801 581 4148                  
> -
> - Department of Mathematics, 110 LCB    Internet e-mail: beebe@math.utah.edu  
> -
> - 155 S 1400 E RM 233                       beebe@acm.org  beebe@computer.org 
> -
> - Salt Lake City, UT 84112-0090, USA    URL: http://www.math.utah.edu/~beebe/ 
> -
> -------------------------------------------------------------------------------