X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fbootchart%2Fsvg.c;h=bf6636cab1d8c26b0c2f9d12a2baac7869faf863;hb=9a6f36c08f1ff93ff861e6371e081122a564c900;hp=81211995292761140f3a9aa7daf90fd8895d7408;hpb=a7997073ac07add6cb30dcd9491c0179b2d6ad52;p=elogind.git

diff --git a/src/bootchart/svg.c b/src/bootchart/svg.c
index 812119952..bf6636cab 100644
--- a/src/bootchart/svg.c
+++ b/src/bootchart/svg.c
@@ -80,6 +80,8 @@ static void svg_header(void) {
         double h;
         struct list_sample_data *sampledata_last;
 
+        assert(head);
+
         sampledata = head;
         LIST_FIND_TAIL(link, sampledata, head);
         sampledata_last = head;