Fix 'Array subscript is above array bounds' GCC warning in GC_new_kind/proc

* misc.c (GC_new_kind_inner, GC_new_proc_inner): Move ABORT call so
that to be immediately followed by return (to workaround
"array subscript is above array bounds" warning reported by MinGW
GCC 4.5.2); do not increase elements count in case of overflow.

1 files changed, 21 insertions, 13 deletions

diff --git a/misc.c b/misc.c
index 6490541e..f41384b2 100644
--- a/misc.c
+++ b/misc.c
@@ -1771,18 +1771,22 @@ GC_API void ** GC_CALL GC_new_free_list(void)
 GC_API unsigned GC_CALL GC_new_kind_inner(void **fl, GC_word descr,
                                           int adjust, int clear)
 {
-    unsigned result = GC_n_kinds++;
-
-    if (GC_n_kinds > MAXOBJKINDS) ABORT("Too many kinds");
-    GC_obj_kinds[result].ok_freelist = fl;
-    GC_obj_kinds[result].ok_reclaim_list = 0;
-    GC_obj_kinds[result].ok_descriptor = descr;
-    GC_obj_kinds[result].ok_relocate_descr = adjust;
-    GC_obj_kinds[result].ok_init = (GC_bool)clear;
-#   ifdef ENABLE_DISCLAIM
+    unsigned result = GC_n_kinds;
+
+    if (result < MAXOBJKINDS) {
+      GC_n_kinds++;
+      GC_obj_kinds[result].ok_freelist = fl;
+      GC_obj_kinds[result].ok_reclaim_list = 0;
+      GC_obj_kinds[result].ok_descriptor = descr;
+      GC_obj_kinds[result].ok_relocate_descr = adjust;
+      GC_obj_kinds[result].ok_init = (GC_bool)clear;
+#     ifdef ENABLE_DISCLAIM
         GC_obj_kinds[result].ok_mark_unconditionally = FALSE;
         GC_obj_kinds[result].ok_disclaim_proc = 0;
-#   endif
+#     endif
+    } else {
+      ABORT("Too many kinds");
+    }
     return result;
 }
 
@@ -1799,10 +1803,14 @@ GC_API unsigned GC_CALL GC_new_kind(void **fl, GC_word descr, int adjust,
 
 GC_API unsigned GC_CALL GC_new_proc_inner(GC_mark_proc proc)
 {
-    unsigned result = GC_n_mark_procs++;
+    unsigned result = GC_n_mark_procs;
 
-    if (GC_n_mark_procs > MAX_MARK_PROCS) ABORT("Too many mark procedures");
-    GC_mark_procs[result] = proc;
+    if (result < MAX_MARK_PROCS) {
+      GC_n_mark_procs++;
+      GC_mark_procs[result] = proc;
+    } else {
+      ABORT("Too many mark procedures");
+    }
     return result;
 }