spv: Fix crash reading a page_setup without headings.

The SPV driver can output such a page_setup.

diff --git a/src/output/spv/spv.c b/src/output/spv/spv.c
index 38abf9775c87cb93ab5e9d385712c8821612d656..eb4d1cd792daf1f85cc204640a8dd7c8da8071c4 100644 (file)
--- a/src/output/spv/spv.c
+++ b/src/output/spv/spv.c
@@ -321,6 +321,9 @@ decode_page_paragraph (const struct spvsx_page_paragraph *page_paragraph,
 {
   memset (ph, 0, sizeof *ph);
 
+  if (!page_paragraph)
+    return;
+
   const struct spvsx_page_paragraph_text *page_paragraph_text
     = page_paragraph->page_paragraph_text;
   if (!page_paragraph_text)