According to Posix, including <unistd.h> should bring in the declaration
of crypt. The glibc and FreeBSD headers are consistent with this, but
Cygwin's aren't.
$ cat test.c
#include <unistd.h>
int
main (void)
{
const char *key = NULL;
const char *salt = NULL;
crypt (key, salt);
}
$ gcc -c test.c
test.c: In function ‘main’:
test.c:8:3: warning: implicit declaration of function ‘crypt’
[-Wimplicit-function-declaration]
crypt (key, salt);
^
The attached patch is one way to fix this. It means that cygwin-devel
would have to require libcrypt-devel.
I'm not sure if I used the right feature-test macro in the patch. It's
marked XSI by Posix, but using __XSI_VISIBLE didn't work.
Ken
P.S. Is cygwin-patches OK for this sort of thing, or should I have sent
it to the newlib list?
From 91ed7816e771a78170555db246e0e35dc6d2ca3e Mon Sep 17 00:00:00 2001
From: Ken Brown <kbr...@cornell.edu>
Date: Wed, 8 Jun 2016 17:04:06 -0400
Subject: [PATCH] Make <unistd.h> declare crypt
This is mandated by Posix and is done by the glibc and FreeBSD headers.
---
newlib/libc/include/sys/unistd.h | 3 +++
1 file changed, 3 insertions(+)
diff --git a/newlib/libc/include/sys/unistd.h b/newlib/libc/include/sys/unistd.h
index ef00575..ebae5d8 100644
--- a/newlib/libc/include/sys/unistd.h
+++ b/newlib/libc/include/sys/unistd.h
@@ -31,6 +31,9 @@ int _EXFUN(close, (int __fildes ));
#if __POSIX_VISIBLE >= 199209
size_t _EXFUN(confstr, (int __name, char *__buf, size_t __len));
#endif
+#if __BSD_VISIBLE && defined(__CYGWIN__)
+#include <crypt.h>
+#endif
#if __XSI_VISIBLE && __XSI_VISIBLE < 700
char * _EXFUN(ctermid, (char *__s ));
#endif
--
2.8.3
