diff --git a/src/docs_writer.cpp b/src/docs_writer.cpp
index 7a12d0875..67d350f24 100644
--- a/src/docs_writer.cpp
+++ b/src/docs_writer.cpp
@@ -265,8 +265,12 @@ gb_internal OdinDocPosition odin_doc_token_pos_cast(OdinDocWriter *w, TokenPos c
 		AstFile *file = global_files[pos.file_id];
 		if (file != nullptr) {
 			OdinDocFileIndex *file_index_found = map_get(&w->file_cache, file);
-			GB_ASSERT(file_index_found != nullptr);
-			file_index = *file_index_found;
+			// NOTE: a documented entity may hold a position in a file belonging to an
+			// imported package. Such files are only in file_cache when -all-packages is
+			// used, so fall back to the reserved "no file" index.
+			if (file_index_found != nullptr) {
+				file_index = *file_index_found;
+			}
 		}
 	}