bug#66709: gzip build fails on s390x because (version 1.13)

[Sarah-Julia Kriesch]

Hi,

we are using gzip 1.13 for builds on openSUSE Tumbleweed.
It is failing for the hardware architecture s390x with the following error 
message:
[  246s] gcc -DHAVE_CONFIG_H -I. -I./lib  -I./lib    -O2 -Wall 
-U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=3 -fstack-protector-strong -funwind-tables 
-fasynchronous-unwind-tables -fstack-clash-protection -Werror=return-type 
-flto=auto -g -fomit-frame-pointer -W -Wall -Wno-unused-parameter 
-Wstrict-prototypes -Wpointer-arith -fPIE -DDFLTCC_LEVEL_MASK=0x7e 
-fprofile-generate -c -o dfltcc.o dfltcc.c
[  246s] dfltcc.c:86:17: error: expected declaration specifiers or '...' before 
numeric constant
[  246s]    86 |   char alignas (8) aligned;
[  246s]       |                 ^
[  246s] dfltcc.c:87:1: warning: no semicolon at end of struct or union
[  246s]    87 | };
[  246s]       | ^
[  246s] dfltcc.c:138:17: error: expected declaration specifiers or '...' 
before numeric constant
[  246s]   138 |   char alignas (8) aligned;
[  246s]       |                 ^
[  246s] dfltcc.c:139:1: warning: no semicolon at end of struct or union
[  246s]   139 | };
[  246s]       | ^
[  246s] make[2]: *** [Makefile:1945: dfltcc.o] Error 1