Severity: minor

This is without transparant qemu emulation, on a x86-64 Linux box.
Command: ./pre-inst-env guix build ustr --target=aarch64-linux-gnu.
(First patch ustr to use "CC=TARGET-gcc").
The package fails to build.  Some parts of the log that seem relevant:

(during configuration)
	sed -e "s,@HAVE_STDINT_H@,$have_stdint_h,g" -e "s,@USE_ASSERT@,$dbg1,g" -e "s,@USE_EOS_MARK@,$dbg2,g" -e "s,@HAVE_64bit_SIZE_MAX@,$sz64,g" -e "s,@HAVE_RETARDED_VSNPRINTF@,$vsnp,g" < ustr-
conf.h.in > ustr-conf-debug.h
/gnu/store/pwcp239kjf7lnj5i4lkdzcfcxwcfyk72-bash-minimal-5.0.16/bin/sh: line 1: ./autoconf_64b: cannot execute binary file: Exec format error
(during compilation

ustr-main.h:204:34: error: #if with no expression
 #if USTR_CONF_HAVE_64bit_SIZE_MAX

Greetings,
Maxime.