cpp /usr/include/threads.h fails; modfl segfaults

[Corinna Vinschen]

On Aug 29 08:52, airplanemath via Cygwin wrote:
> Hello,
> 
> I have two reports.  A brief description of the system:
> $ uname -a | sed "s/${HOSTNAME}/\${HOSTNAME}/g"
> CYGWIN_NT-10.0 ${HOSTNAME} 3.1.7(0.340/5/3) 2020-08-22 17:48 x86_64 Cygwin
> 
> The first report:
> 
> $ cpp /usr/include/threads.h
> # 1 "/usr/include/threads.h"
> # 1 "<built-in>"
> # 1 "<command-line>"
> # 1 "/usr/include/threads.h"
> /usr/include/threads.h:30:10: fatal error: machine/_threads.h: No such
> file or directory
>    30 | #include <machine/_threads.h>
>       |          ^~~~~~~~~~~~~~~~~~~~
> compilation terminated.

The reason for this is, as Ken already pointed out, that
machine/_threads.h only existed for RTEMS, not for any other target
supported by newlib.  Worse, Cygwin never got around to implement the
C11 threads functions yet.

I added these functions as wrappers around pthread functionality, code
taken from FreeBSD.  I ran the glibc testsuite on them, and after fixing
the bugs in the glibc testsuite (d'oh), the tests ran successfully.

> $ cat test.c
> #include <math.h>
> #include <stdio.h>
> #include <stdlib.h>
> 
> int main(int argc, char *argv[]) {
>   long double a, b, c;
>   char *num_end = NULL;
>   a = b = c = 0.0L;
>   if (argc != 2) {
>     fprintf(stderr, "Usage: %s NUMBER\n", argv[0]);
>     exit(1);
>   }
>   a = strtold(argv[1], &num_end);
>   b = modfl(a, &c);
>   printf("%Lf %Lf %Lf\n", a, b, c);
>   return 0;
> }

This is a bug in the assembler code taken from Mingw-w64.  The bug has
been fixed upstream, so I just pulled in the upstream fixes.

Thus, both of the above problems should be fixed now.  I created a
developer snapshot and uploaed it to https://cygwin.com/snapshots/ You
need to grab the full tar file and install at least the following files
to your installation after backing up the original files from 3.1.7:

  usr/bin/cygwin1.dll	(this is pre-release 3.2.0)
  usr/lib/libcygwin.a
  usr/include/limits.h
  usr/include/pthread.h
  usr/include/machine/_threads.h

Thanks for the report.


Corinna

-- 
Corinna Vinschen
Cygwin Maintainer