[subset] Check for the Null table and not nullptr to detect failure to find a table in glyf accelerator.
diff --git a/src/hb-ot-glyf-table.hh b/src/hb-ot-glyf-table.hh
index 11c3eaa..7946706 100644
--- a/src/hb-ot-glyf-table.hh
+++ b/src/hb-ot-glyf-table.hh
@@ -236,9 +236,9 @@
hb_blob_t *head_blob = Sanitizer<head>().sanitize (face->reference_table (HB_OT_TAG_head));
const head *head_table = Sanitizer<head>::lock_instance (head_blob);
- if (!head_table || (unsigned int) head_table->indexToLocFormat > 1 || head_table->glyphDataFormat != 0)
+ if (head_table == &Null(head) || (unsigned int) head_table->indexToLocFormat > 1 || head_table->glyphDataFormat != 0)
{
- /* Unknown format. Leave num_glyphs=0, that takes care of disabling us. */
+ /* head table is not present, or in an unknown format. Leave num_glyphs=0, that takes care of disabling us. */
hb_blob_destroy (head_blob);
return;
}
@@ -268,7 +268,7 @@
inline bool get_composite (hb_codepoint_t glyph,
CompositeGlyphHeader::Iterator *composite /* OUT */) const
{
- if (!this->glyf_table || !num_glyphs)
+ if (this->glyf_table == &Null(glyf) || !num_glyphs)
return false;
unsigned int start_offset, end_offset;
