1 files changed, 1 insertions, 1 deletions

diff --git a/coreutils/cal.c b/coreutils/cal.c
index f6578bf43..3ccd3fff5 100644
--- a/coreutils/cal.c
+++ b/coreutils/cal.c
@@ -372,7 +372,7 @@ void trim_trailing_spaces(char *s)
 
         for (p = s; *p; ++p)
                 continue;
-        while (p > s && isspace(*--p))
+        while (p > s && (--p, isspace(*p)))
                 continue;
         if (p > s)
                 ++p;