Re: [PATCH] Prototype initstate() etc. if _XOPEN_SOURCE is defined appropriately

[Jon TURNEY]

On 13/11/2013 14:37, Jon TURNEY wrote:

Not sure if this is wanted, but mesa likes to compile with '-std=c99
D_XOPEN_SOURCE=500', which leads to exciting crashes on x86_64 because
initstate() is not prototyped.

2013-11-13  Jon TURNEY  <jon.tur...@dronecode.org.uk>

        * include/cygwin/stdlib.h(initstate, random, setstate, srandom) :
        Prototype if not __STRICT_ANSI__ or _XOPEN_SOURCE is defined 
appropriately.

It seems this doesn't do the correct thing if _GNU_SOURCE is defined 
(which is supposed to imply _XOPEN_SOURCE)

Attached is an additional patch which instead includes sys/cdefs.h, and 
uses __XSI_VISIBLE.

$ cat test.c

#include <stdlib.h>

int main()
{
 return random();
}

before:

$ gcc test.c -Wall -ansi -D_GNU_SOURCE
test.c: In function ‘main’:
test.c:6:2: warning: implicit declaration of function ‘random’

after:

$ gcc test.c -Wall -ansi -D_GNU_SOURCE

2015-02-19  Jon TURNEY  <jon.tur...@dronecode.org.uk>

        * include/cygwin/stdlib.h (initstate, random, setstate, srandom):
        Check if __XSI_VISIBLE is set by sys/cdefs.h, rather than testing
        for _XOPEN_SOURCE directly, to work correctly when _GNU_SOURCE is
        set.

Index: cygwin/include/cygwin/stdlib.h
===================================================================
RCS file: /cvs/src/src/winsup/cygwin/include/cygwin/stdlib.h,v
retrieving revision 1.17
diff -u -u -p -r1.17 stdlib.h
--- cygwin/include/cygwin/stdlib.h      9 Dec 2013 10:12:42 -0000       1.17
+++ cygwin/include/cygwin/stdlib.h      19 Feb 2015 12:41:00 -0000
@@ -11,6 +11,7 @@ details. */
 #ifndef _CYGWIN_STDLIB_H
 #define _CYGWIN_STDLIB_H
 
+#include <sys/cdefs.h>
 #include <cygwin/wait.h>
 
 #ifdef __cplusplus
@@ -31,9 +32,7 @@ void  setprogname (const char *);
 char *canonicalize_file_name (const char *);
 int unsetenv (const char *);
 #endif /*__STRICT_ANSI__*/
-#if !defined(__STRICT_ANSI__) \
-    || (defined(_XOPEN_SOURCE) \
-       && ((_XOPEN_SOURCE - 0 >= 500) || defined(_XOPEN_SOURCE_EXTENDED)))
+#if !defined(__STRICT_ANSI__) || (__XSI_VISIBLE >= 500)
 char *initstate (unsigned seed, char *state, size_t size);
 long random (void);
 char *setstate (const char *state);