Fix array index out of bounds.

[lightning.git] / slicenumpy.go

diff --git a/slicenumpy.go b/slicenumpy.go
index 88fd817537a3020552e04032a345cef2d7ba0bc8..2fc2fd6149c0bf546a758cd58b99d8f3535971c8 100644 (file)
--- a/slicenumpy.go
+++ b/slicenumpy.go
@@ -263,8 +263,10 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
                                        count := make([]tileVariantID, len(variants))
                                        for _, cg := range cgs {
                                                idx := (tag - tagstart) * 2
-                                               count[cg.Variants[idx]]++
-                                               count[cg.Variants[idx+1]]++
+                                               if int(idx) < len(cg.Variants) {
+                                                       count[cg.Variants[idx]]++
+                                                       count[cg.Variants[idx+1]]++
+                                               }
                                        }
                                        ranked := make([]tileVariantID, len(variants))
                                        for i := range ranked {