compat UPDATE add alloca.h check

Author: michalvasko

CMakeModules/UseCompat.cmake

@@ -67,6 +67,8 @@ macro(USE_COMPAT)
 
     check_function_exists(timegm HAVE_TIMEGM)
 
+    check_include_file("alloca.h" HAVE_ALLOCA_H)
+
     # crypt
     check_include_file("crypt.h" HAVE_CRYPT_H)
 

compat/compat.h.in

@@ -3,7 +3,7 @@
  * @author Michal Vasko <[email protected]>
  * @brief compatibility functions header
  *
- * Copyright (c) 2021 - 2023 CESNET, z.s.p.o.
+ * Copyright (c) 2021 - 2025 CESNET, z.s.p.o.
  *
  * This source code is licensed under BSD 3-Clause License (the "License").
  * You may not use this file except in compliance with the License.
@@ -18,12 +18,15 @@
 #define _GNU_SOURCE /* pthread_rwlock_t */
 
 #cmakedefine HAVE_CRYPT_H
-
 #ifdef HAVE_CRYPT_H
-#   include <crypt.h>
+# include <crypt.h>
+#endif
+
+#cmakedefine HAVE_ALLOCA_H
+#ifdef HAVE_ALLOCA_H
+# include <alloca.h>
 #endif
 
-#include <alloca.h>
 #include <limits.h>
 #include <pthread.h>
 #include <stdarg.h>