[PATCH] Fix Ada bootstrap failure on Cygwin since switch to C++11 (PR98590)

gcc/ada
	PR bootstrap/98590
	* cstreams.c: Ensure fileno_unlocked() is visible on Cygwin.

diff --git a/gcc/ada/cstreams.c b/gcc/ada/cstreams.c
index 4e00ded..8072320 100644 (file)
--- a/gcc/ada/cstreams.c
+++ b/gcc/ada/cstreams.c
@@ -37,6 +37,11 @@
 #define _FILE_OFFSET_BITS 64
 /* the define above will make off_t a 64bit type on GNU/Linux */
 
+/* Tell Cygwin's <stdio.h> to expose fileno_unlocked() */
+#if defined(__CYGWIN__) && !defined(__CYGWIN32__) && !defined(_GNU_SOURCE)
+#define _GNU_SOURCE
+#endif
+
 #include <stdio.h>
 #include <sys/types.h>
 #include <sys/stat.h>