[newlib-cygwin] Restore _lock initialization in non-single threaded mode

[newlib-cygwin] Restore _lock initialization in non-single threaded mode

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=dd1122e21cb4ea78ce4c5894787c8f085469f9dd

commit dd1122e21cb4ea78ce4c5894787c8f085469f9dd
Author: Torbjörn SVENSSON <torbjorn.svensson@foss.st.com>
Date:   Tue Aug 30 15:54:53 2022 +0200

    Restore _lock initialization in non-single threaded mode
    
    When __SINGLE_THREAD__ is not defined, stdin, stdout and stderr needs
    to have their _lock instance initialized. The __sfp() method is not
    invoked for the 3 mentioned fds thus, the std() method needs to handle
    the initialization of the lock.
    
    This is more or less a revert of 382550072b49430f8c69adee937a0ba07bd385e6
    
    Contributed by STMicroelectronics
    
    Signed-off-by: Torbjörn SVENSSON <torbjorn.svensson@foss.st.com>

Diff:
---
 newlib/libc/stdio/findfp.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/newlib/libc/stdio/findfp.c b/newlib/libc/stdio/findfp.c
index c43028209..2cc549537 100644
--- a/newlib/libc/stdio/findfp.c
+++ b/newlib/libc/stdio/findfp.c
@@ -88,6 +88,10 @@ std (FILE *ptr,
 #else /* _STDIO_CLOSE_STD_STREAMS */
   ptr->_close = NULL;
 #endif /* _STDIO_CLOSE_STD_STREAMS */
+#ifndef __SINGLE_THREAD__
+  if (ptr == &__sf[0] || ptr == &__sf[1] || ptr == &__sf[2])
+    __lock_init_recursive (ptr->_lock);
+#endif
 #ifdef __SCLE
   if (__stextmode (ptr->_file))
     ptr->_flags |= __SCLE;