1 files changed, 10 insertions, 8 deletions
diff --git a/gc.c b/gc.c
index 9801a19adb..3defaab7c7 100644
--- a/gc.c
+++ b/gc.c
@@ -36,17 +36,19 @@ void rb_io_fptr_finalize _((struct OpenFile*));
 #  endif
 # endif /* atarist */
 #else
-# if defined(HAVE_ALLOCA_H)
+# ifdef HAVE_ALLOCA_H
 #  include <alloca.h>
-# elif !defined(alloca)
-void *alloca();
-# endif
+# else
+#  ifdef _AIX
+ #pragma alloca
+#  else
+#   ifndef alloca /* predefined by HP cc +Olibcalls */
+void *alloca ();
+#   endif
+#  endif /* AIX */
+# endif /* HAVE_ALLOCA_H */
 #endif /* __GNUC__ */
 
-#ifdef _AIX
-#pragma alloca
-#endif
-
 static void run_final();
 
 #ifndef GC_MALLOC_LIMIT