When testing whether kernel could be build from its SRPM if one sets
/bin/sh to ksh I've found that it doesn't work.

The process ends up with:

+ mkdir -p
/home/builder/rpmbuild/BUILDROOT/kernel-uek-4.14.32-1.el7uek.aarch64/usr/lib/d
ebug/boot
+ mkdir -p
/home/builder/rpmbuild/BUILDROOT/kernel-uek-4.14.32-1.el7uek.aarch64/usr/lib/d
ebug/boot
+ mkdir -p
/home/builder/rpmbuild/BUILDROOT/kernel-uek-4.14.32-1.el7uek.aarch64/boot
+ install -m 644 .config
/home/builder/rpmbuild/BUILDROOT/kernel-uek-4.14.32-1.el7uek.aarch64/boot/conf
ig-4.14.32-1.el7uek.aarch64.debug
+ install -m 644 System.map
/home/builder/rpmbuild/BUILDROOT/kernel-uek-4.14.32-1.el7uek.aarch64/boot/Syst
em.map-4.14.32-1.el7uek.aarch64.debug
+ touch
/home/builder/rpmbuild/BUILDROOT/kernel-uek-4.14.32-1.el7uek.aarch64/boot/init
ramfs-4.14.32-1.el7uek.aarch64.debug.img
+ [ -f arch/arm64/boot/zImage.stub ]
+ [ -x /usr/bin/pesign ]
+ [ aarch64 '==' x86_64 -o aarch64 '==' aarch64 ]
+ [ 07 -ge 7 -a -f /usr/bin/rpm-sign ]
+ [ -S /var/run/pesign/socket ]
+ /usr/bin/pesign -c 'Oracle Linux Test Certificate' -i arch/arm64/boot/Image
-o arch/arm64/boot/Image.signed -s
+ [ ! -s -o arch/arm64/boot/Image.signed ]
+ [ -e arch/arm64/boot/Image.signed ]
+ rm -f arch/arm64/boot/Image.signed
+ exit 1
error: Bad exit status from /var/tmp/rpm-tmp.2u96Jp (%build)


RPM build errors:
    Bad exit status from /var/tmp/rpm-tmp.2u96Jp (%build)

Inspecting where the construct [ ! -s -o arch/arm64/boot/Image.signed ] comes
from points to /etc/rpm/macros.pesign and this snippet of the macro's code:

  if [ ! -s %{-o} ]; then \
    if [ -e "%{-o*}" ]; then \
      rm -f %{-o*} \
    fi \
    exit 1 \
  fi ;

Perhaps the author wanted to verify there is a non-zero length output file.
Otherwise remove it if it exists with zero length and fail. Unfortunately
%{-o} expands to the full flag not only the value. That is it produced
[ ! -s -o arch/arm64/boot/Image.signed ] that is wrong and moreover behaves
differently in bash and ksh:

[builder@g0 ~]$ echo "xxxx" > /tmp/a
[builder@g0 ~]$ [ ! -s -o /tmp/a ] ; echo $?
1
[builder@g0 ~]$ ksh
$ [ ! -s -o /tmp/a ] ; echo $?
0

The correction is to use "%{-o*}".