[gnome-builder] clang: don't call g_strv_length() on NULL array

[Christian Hergert <chergert src gnome org>]

commit 279059e18e7759728f90e8e4c36d685e1b972b73
Author: Christian Hergert <chergert redhat com>
Date:   Thu Jan 25 03:44:57 2018 -0800

    clang: don't call g_strv_length() on NULL array

 src/plugins/clang/ide-clang-code-indexer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/plugins/clang/ide-clang-code-indexer.c b/src/plugins/clang/ide-clang-code-indexer.c
index f2bce689d..84e35ca8e 100644
--- a/src/plugins/clang/ide-clang-code-indexer.c
+++ b/src/plugins/clang/ide-clang-code-indexer.c
@@ -64,7 +64,7 @@ ide_clang_code_indexer_index_file_worker (GTask        *task,
   code = clang_parseTranslationUnit2 (index,
                                       path,
                                       (const char * const *)br->build_flags,
-                                      g_strv_length (br->build_flags),
+                                      br->build_flags ? g_strv_length (br->build_flags) : 0,
                                       NULL,
                                       0,
                                       (CXTranslationUnit_DetailedPreprocessingRecord |