Feature test macros overhaul: Cygwin headers

Use proper internal macros for BSD and GNU.

Signed-off-by: Yaakov Selkowitz <yselkowi@redhat.com>

winsup/cygwin/include/endian.h

@@ -12,6 +12,7 @@ details. */
 #define _ENDIAN_H_
 
 #include <sys/config.h>
+#include <sys/cdefs.h>
 #include <bits/endian.h>
 
 /*#ifdef  __USE_BSD*/
@@ -27,7 +28,7 @@ details. */
 # define __LONG_LONG_PAIR(HI, LO) HI, LO
 #endif
 
-#if /*defined __USE_BSD ||*/ ! defined _POSIX_SOURCE
+#if __BSD_VISIBLE
 
 #include <byteswap.h>
 
@@ -71,7 +72,7 @@ details. */
 
 #endif /*__BYTE_ORDER == __BIG_ENDIAN*/
 
-#endif /*__USE_BSD || !_POSIX_SOURCE*/
+#endif /*__BSD_VISIBLE*/
 
 #endif /*_ENDIAN_H_*/
 

winsup/cygwin/include/fenv.h

@@ -11,6 +11,8 @@ details. */
 #ifndef _FENV_H_
 #define _FENV_H_
 
+#include <sys/cdefs.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -133,14 +135,14 @@ extern const fenv_t *_fe_dfl_env;
    type "pointer to const-qualified fenv_t",may also be specified by
    the implementation.  */
 
-#ifdef _GNU_SOURCE
+#if __GNU_VISIBLE
 /*  If possible, the GNU C Library defines a macro FE_NOMASK_ENV which
    represents an environment where every exception raised causes a trap
    to occur. You can test for this macro using #ifdef. It is only defined
    if _GNU_SOURCE is defined.  */
 extern const fenv_t *_fe_nomask_env;
 #define FE_NOMASK_ENV (_fe_nomask_env)
-#endif /* _GNU_SOURCE */
+#endif /* __GNU_VISIBLE */
 
 
 /*  The following shall be declared as functions and may also be

winsup/cygwin/include/glob.h

@@ -80,7 +80,7 @@ typedef struct {
 #define	GLOB_NOMATCH	(-3)	/* No match and GLOB_NOCHECK was not set. */
 #define	GLOB_NOSYS	(-4)	/* Obsolete: source comptability only. */
 
-#ifndef _POSIX_SOURCE
+#if __GNU_VISIBLE
 #define	GLOB_ALTDIRFUNC	0x0040	/* Use alternately specified directory funcs. */
 #define	GLOB_BRACE	0x0080	/* Expand braces ala csh. */
 #define	GLOB_MAGCHAR	0x0100	/* Pattern had globbing characters. */
@@ -92,7 +92,7 @@ typedef struct {
 /* source compatibility, these are the old names */
 #define GLOB_MAXPATH	GLOB_LIMIT
 #define	GLOB_ABEND	GLOB_ABORTED
-#endif /* __BSD_VISIBLE */
+#endif /* __GNU_VISIBLE */
 
 __BEGIN_DECLS