doc/sod.tex: Cope if `\pkgversion' isn't defined.

diff --git a/doc/sod.tex b/doc/sod.tex
index 1203b68..c689bc9 100644 (file)
--- a/doc/sod.tex
+++ b/doc/sod.tex
@@ -53,6 +53,11 @@
 \let\indexstheadcase\relax
 \bibliographystyle{mdwalpha}
 
+\ifx\pkgversion\xxundefined
+  \immediate\typeout{WARNING: \string\pkgversion\ not defined}
+  \def\pkgversion{UNSET}
+\fi
+
 \title{A Sensible Object Design for C}
 \author{Mark Wooding}
 \date{\today; version \pkgversion}