[RFA] enable dynamic (thread safe) reents

Christopher Faylor cgf@redhat.com
Fri Jun 13 14:14:00 GMT 2003

On Fri, Jun 13, 2003 at 08:20:47AM +0200, Thomas Pfaff wrote:
>Christopher Faylor wrote:
>>On Fri, May 16, 2003 at 02:12:16PM +0200, Thomas Pfaff wrote:
>>>Thomas Pfaff wrote:
>>>>While single threaded apps should keep run without problems (_impure_ptr
>>>>is still used for the mainthread) multithreaded apps should be recompiled
>>>>to get the full power of the thread safe reents. This is due the
>>>>fact that _RRENT is used in some newlib headers directly. Unfortunately
>>>>this affects also static libs, therefore this is will be a longer
>>>this will only affect stdio
>>>stdio.h:147:#define     stdin   (_REENT->_stdin)
>>>stdio.h:148:#define     stdout  (_REENT->_stdout)
>>>stdio.h:149:#define     stderr  (_REENT->_stderr)
>>>and i consider this harmless.
>>Does this imply that using a DLL rebuilt like this will require 
>>of static libraries using errno?
>No. errno is handled differently.
>#ifndef _REENT_ONLY
>#define errno (*__errno())
>extern int *__errno _PARAMS ((void));
>and __errno is in newlib implemented as
>int *
>__errno ()
>  return &_REENT->_errno;
>Therefore threads safe errnos are automatically enabled when newlib is 
>compiled with __DYNAMIC_REENT__.
>Unfortunately stdin, stdout and stderr were defined with _REENT 
>directly. Sigh.

Should we submit a patch to newlib which fixes this?


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