Merge commit 'd6a27f885b5d4cba7a82e50af423c741d2f37c3e'

* commit 'd6a27f885b5d4cba7a82e50af423c741d2f37c3e':
  configure: Add usan to the toolchain presets

Merged-by: Michael Niedermayer <michaelni@gmx.at>

configure

@@ -2758,6 +2758,11 @@ case "$toolchain" in
         add_cflags  -fsanitize=thread -pie
         add_ldflags -fsanitize=thread -pie
     ;;
+    clang-usan)
+        cc_default="clang"
+        add_cflags  -fsanitize=undefined
+        add_ldflags -fsanitize=undefined
+    ;;
     gcc-asan)
         cc_default="gcc"
         add_cflags  -fsanitize=address
@@ -2768,6 +2773,11 @@ case "$toolchain" in
         add_cflags  -fsanitize=thread -pie -fPIC
         add_ldflags -fsanitize=thread -pie -fPIC
     ;;
+    gcc-usan)
+        cc_default="gcc"
+        add_cflags  -fsanitize=undefined
+        add_ldflags -fsanitize=undefined
+    ;;
     valgrind-massif)
         target_exec_default=${valgrind:-"valgrind"}
         target_exec_args="--tool=massif --alloc-fn=av_malloc --alloc-fn=av_mallocz --alloc-fn=av_calloc --alloc-fn=av_fast_padded_malloc --alloc-fn=av_fast_malloc --alloc-fn=av_realloc_f --alloc-fn=av_fast_realloc --alloc-fn=av_realloc"