Fix GC bugs related to uninitialized vectors

Avoid problems if GC occurs while initializing a vector.
Problem with Fdelete reported by Pip Cet in:
https://lists.gnu.org/r/emacs-devel/2020-08/msg00313.html
I looked for similar problems elsewhere and found quite a few.
* src/coding.c (make_subsidiaries):
* src/composite.c (syms_of_composite):
* src/font.c (build_style_table, Ffont_get_glyphs):
* src/nsselect.m (clean_local_selection_data):
* src/nsxwidget.m (js_to_lisp):
* src/syntax.c (init_syntax_once):
* src/window.c (Fcurrent_window_configuration):
* src/xselect.c (selection_data_to_lisp_data)
(clean_local_selection_data):
Use make_nil_vector instead of make_uninit_vector.
* src/fns.c (Fdelete):
* src/xwidget.c (webkit_js_to_lisp):
Use allocate_nil_vector instead of allocate_vector.
* src/search.c (Fnewline_cache_check):
Use make_vector instead of make_uninit_vector.

1 files changed, 3 insertions, 6 deletions

diff --git a/src/coding.c b/src/coding.c
index 1d79c703a3a..51bd441de9d 100644
--- a/src/coding.c
+++ b/src/coding.c
@@ -10856,20 +10856,17 @@ HIGHESTP non-nil means just return the highest priority one.  */)
   return Fnreverse (val);
 }
 
-static const char *const suffixes[] = { "-unix", "-dos", "-mac" };
-
 static Lisp_Object
 make_subsidiaries (Lisp_Object base)
 {
-  Lisp_Object subsidiaries;
+  static char const suffixes[][8] = { "-unix", "-dos", "-mac" };
   ptrdiff_t base_name_len = SBYTES (SYMBOL_NAME (base));
   USE_SAFE_ALLOCA;
   char *buf = SAFE_ALLOCA (base_name_len + 6);
-  int i;
 
   memcpy (buf, SDATA (SYMBOL_NAME (base)), base_name_len);
-  subsidiaries = make_uninit_vector (3);
-  for (i = 0; i < 3; i++)
+  Lisp_Object subsidiaries = make_nil_vector (3);
+  for (int i = 0; i < 3; i++)
     {
       strcpy (buf + base_name_len, suffixes[i]);
       ASET (subsidiaries, i, intern (buf));