[gegl] operations/external/raw-load: Be more assertive about what we expect

[Debarshi Ray <debarshir src gnome org>]

commit c518ad0fb7ce70b00a5f74a916f000db83bcfa48
Author: Debarshi Ray <debarshir gnome org>
Date:   Sat Feb 4 02:13:19 2017 +0100

    operations/external/raw-load: Be more assertive about what we expect
    
    Unless there is a programmer error, there is no reason for the
    libraw_processed_image_t (ie. p->image) to be anything other than NULL
    when the libraw_data_t (ie. p->LibRaw) is NULL. Therefore let's assert
    it because an assignment might mask a potential bug.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=778160

 operations/external/raw-load.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/operations/external/raw-load.c b/operations/external/raw-load.c
index d2fb095..d2c739a 100644
--- a/operations/external/raw-load.c
+++ b/operations/external/raw-load.c
@@ -90,7 +90,7 @@ prepare (GeglOperation *operation)
 
   if (p->LibRaw == NULL)
     {
-      p->image = NULL;
+      g_return_if_fail (p->image == NULL);
 
       if ((p->LibRaw = libraw_init(LIBRAW_OPTIONS_NONE)) == NULL)
         g_warning ("raw-load: Error Initializing raw library");