X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fplot-hist.c;h=6b2e7f9f177bfe74523dc67448a39e75c882d47d;hb=05e356b2a3087e819ef3b5388e29c822f41502e1;hp=ebfcd3f107e6984a0a929053000600a6525bb2a9;hpb=a7cc8b259f0fe963aa30d4e64f7d39551ded1454;p=pspp-builds.git

diff --git a/src/plot-hist.c b/src/plot-hist.c
index ebfcd3f1..6b2e7f9f 100644
--- a/src/plot-hist.c
+++ b/src/plot-hist.c
@@ -39,6 +39,9 @@ void
 histogram_write_legend(struct chart *ch, const struct normal_curve *norm)
 {
   char buf[100];
+  if ( !ch )
+	  return ;
+
   pl_savestate_r(ch->lp);
 
   sprintf(buf,"N = %.2f",norm->N);
@@ -66,6 +69,8 @@ hist_draw_bar(struct chart *ch, const gsl_histogram *hist, int bar)
   double lower;
   double height;
 
+  if ( !ch ) 
+	  return ;
   const size_t bins = gsl_histogram_bins(hist);
   const double x_pos = (ch->data_right - ch->data_left) * bar / (double) bins ;
   const double width = (ch->data_right - ch->data_left) / (double) bins ;