[PATCH -perfbook 1/6] runlatex.sh: Cope with missing cleveref.sty

Since commit 1bc3abddbf59 ("Stop using "cleveref" with LaTeX2e
<2024-11-01> and later"), building perfbook doesn't need cleveref.

Warning on old cleveref can be skipped now.

Signed-off-by: Akira Yokosawa <[email protected]>
---
 utilities/runlatex.sh | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/utilities/runlatex.sh b/utilities/runlatex.sh
index 9a060897..7e074c9f 100644
--- a/utilities/runlatex.sh
+++ b/utilities/runlatex.sh
@@ -184,14 +184,17 @@ else
 	echo "'$basename.pdf' is ready, with above warning(s) ignored."
 fi
 # cleveref version check (Ubuntu 18.04 LTS has buggy one
-if grep -q -F "packageversion{0.21.1}" `kpsewhich cleveref.sty`
-then
+CLEVEREF_STY=`kpsewhich cleveref.sty`
+if [ "$CLEVEREF_STY" != "" ] ; then
+    if grep -q -F "packageversion{0.21.1}" $CLEVEREF_STY
+    then
 	echo "############################################################"
 	echo "### Buggy version of LaTeX package 'cleveref' detected!! ###"
 	echo "### (Known issue on Ubuntu 18.04 LTS)                    ###"
 	echo "### Required TeX Live is 2019/Debian or later.           ###"
 	echo "### Consider upgrading to Ubuntu 20.04 LTS or later.     ###"
 	echo "############################################################"
+    fi
 fi
 # to avoid redundant run of bibtex and pdflatex
 touch $basename.bbl
-- 
2.43.0