The following patch fixes

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97983

The patch was successfully bootstrapped on x86_64 and s390x (with 
--enable-languages=c,c++ --enable-checking=release --disable-multilib 
--with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions 
--enable-gnu-unique-object --enable-linker-build-\
id --with-gcc-major-version-only --with-linker-hash-style=gnu 
--enable-plugin --enable-initfini-array --with-isl 
--enable-gnu-indirect-function --with-long-double-128 --with-arch=zEC12 
--with-tune=z13 --enable-decimal-float)