Re: make release failure on releng/15.0

It looks like there is a known issue:
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=294729

However I'm not building a custom kernel, so the issue may have other
root causes, i.e. specific src.conf settings?. The way I build:

BUILD_DIR="/home/user/freebsd"
MACHINE=amd64
MACHINE_ARCH=amd64
FREEBSD_SRC="${BUILD_DIR:?}/src"
FREEBSD_OBJ="${BUILD_DIR:?}/obj"

# Generate src.conf
cat > ${BUILD_DIR:?}/src.conf << 'EOF'
# Enable non-default settings
WITH_BHYVE_SNAPSHOT=yes
WITH_OFED_EXTRA=yes
WITH_REPRODUCIBLE_BUILD=yes
WITH_MALLOC_PRODUCTION=yes

# Disable default settings
WITHOUT_FREEBSD_UPDATE=yes
WITHOUT_LIB32=yes
WITHOUT_TESTS=yes
WITHOUT_TESTS_SUPPORT=yes
EOF

# Build everything
env \
  MAKEOBJDIRPREFIX=${FREEBSD_OBJ:?} SRCCONF="${BUILD_DIR:?}/src.conf" SYSDIR="${FREEBSD_SRC:?}/sys" \
  make -C ${FREEBSD_SRC:?} TARGET=${MACHINE:?} TARGET_ARCH=${MACHINE_ARCH:?} \
    -j 12 buildworld buildkernel > ${BUILD_DIR:?}/build.log 2>&1 \
    || echo "ERROR: make failed"

# Create release
env \
  MAKEOBJDIRPREFIX=${FREEBSD_OBJ:?} SRCCONF="${BUILD_DIR:?}/src.conf" SYSDIR="${FREEBSD_SRC:?}/sys" \
  make -C ${FREEBSD_SRC:?}/release TARGET=${MACHINE:?} TARGET_ARCH=${MACHINE_ARCH:?} \
    release > ${BUILD_DIR:?}/release.log 2>&1 \
    || echo "ERROR: make failed"