unoptimized -fsanitize=undefined build on clang requires more stack space

CMakeLists.txt

@@ -216,7 +216,7 @@ ENDIF()
 
 OPTION(WITH_UBSAN "Enable undefined behavior sanitizer" OFF)
 IF (WITH_UBSAN)
-  MY_CHECK_AND_SET_COMPILER_FLAG("-fsanitize=undefined -fno-sanitize=alignment -U_FORTIFY_SOURCE" DEBUG RELWITHDEBINFO)
+  MY_CHECK_AND_SET_COMPILER_FLAG("-fsanitize=undefined -fno-sanitize=alignment -U_FORTIFY_SOURCE -DWITH_UBSAN" DEBUG RELWITHDEBINFO)
 ENDIF()
 
 OPTION(WITH_MSAN "Enable memory sanitizer" OFF)

include/my_pthread.h

@@ -693,7 +693,7 @@ extern void my_mutex_end(void);
   We need to have at least 256K stack to handle calls to myisamchk_init()
   with the current number of keys and key parts.
 */
-#ifdef __SANITIZE_ADDRESS__
+#if defined(__SANITIZE_ADDRESS__) || defined(WITH_UBSAN)
 #define DEFAULT_THREAD_STACK	(364*1024L)
 #else
 #define DEFAULT_THREAD_STACK	(292*1024L)