Add CONST_CAST macro, for casting away "const" more safely.

[pspp] / src / output / chart.c

diff --git a/src/output/chart.c b/src/output/chart.c
index e1832e20bb39154ea36ecd702a7bc5cc68253a80..1f85d8e485d2303f1cbce08523247d854583a1e9 100644 (file)
--- a/src/output/chart.c
+++ b/src/output/chart.c
@@ -142,7 +142,7 @@ chart_draw_png (const struct chart *chart, const char *file_name_template,
 struct chart *
 chart_ref (const struct chart *chart_)
 {
-  struct chart *chart = (struct chart *) chart_;
+  struct chart *chart = CONST_CAST (struct chart *, chart_);
   chart->ref_cnt++;
   return chart;
 }