1 files changed, 1 insertions, 1 deletions

diff --git a/src/plugins/odf_extractor.c b/src/plugins/odf_extractor.c
index 4ac3e91..cd75c2a 100644
--- a/src/plugins/odf_extractor.c
+++ b/src/plugins/odf_extractor.c
@@ -93,7 +93,7 @@ libextractor_oo_getmimetype(EXTRACTOR_unzip_file uf) {
         /* found something */
         buf[buf_size] = '\0';
         while ( (0 > buf_size) &&
-                isspace(buf[buf_size - 1]))
+                isspace( (unsigned char) buf[buf_size - 1]))
           buf[--buf_size] = '\0';
         if('\0' == buf[0]) {
           free(buf);