Fix trivial regression in last commit.
diff --git a/libdw/dwarf_getmacros.c b/libdw/dwarf_getmacros.c
index 22afbc3..4220ebe 100644
--- a/libdw/dwarf_getmacros.c
+++ b/libdw/dwarf_getmacros.c
@@ -65,6 +65,9 @@
      void *arg;
      ptrdiff_t offset;
 {
+  if (d == NULL)
+    return -1;
+
   Elf_Data *d = die->cu->dbg->sectiondata[IDX_debug_macinfo];
   if (unlikely (d == NULL) || unlikely (d->d_buf == NULL))
     {