fixed failed assertion in exif_free

diff --git a/src/exiv2.cc b/src/exiv2.cc
index 07b5afa..45bcf52 100644 (file)
--- a/src/exiv2.cc
+++ b/src/exiv2.cc
@@ -352,6 +352,7 @@ int exif_write(ExifData *exif)
 
 void exif_free(ExifData *exif)
 {
+       if (!exif) return;
        g_assert(dynamic_cast<_ExifDataProcessed *>(exif)); // this should not be called on ExifDataOriginal
        delete exif;
 }