[Bug ada/82393] Compilation error on cygwin64

["didu31 at hotmail dot fr" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82393

--- Comment #12 from Didier G <didu31 at hotmail dot fr> ---
(In reply to Eric Botcazou from comment #9)
> > Trace of check ada runtests
> 
> You can do 'make mail-report.log' after 'make -k check' to have a report.
> 
> The results are acceptable although gnat.dg/entry_queues.adb and c380004,
> which probably come from the same underlying issue, would need to be
> investigated.

FYI, to make you an idea of the c380004's failure, a SEGV occurs in
cygwin.S:___chkstk_ms, caused by stack check at c380004.adb:132.

The trace, here :

Starting program: /home/didier/c380004.exe
[New Thread 11216.0x1fc4]
[New Thread 11216.0x1e4]
[New Thread 11216.0x2794]
[New Thread 11216.0x1f00]

,.,. C380004 ACATS 2.5 17-10-05 11:45:34
---- C380004 Check evaluation of discriminant expressions when the
                constraint depends on a discriminant, and the
                discriminants have defaults -
                discriminant-dependententry families and protected
                components.
   - C380004 Discriminant-dependent entry families for task types.
[New Thread 11216.0x1b6c]
[New Thread 11216.0x265c]
[Thread 11216.0x1b6c exited with code 1]
[Thread 11216.0x265c exited with code 1]
[New Thread 11216.0x15a4]
[Thread 11216.0x15a4 exited with code 1]
[New Thread 11216.0xac4]
[Thread 11216.0xac4 exited with code 1]
[New Thread 11216.0x34e8]
[Thread 11216.0x34e8 exited with code 1]
[New Thread 11216.0x2170]
[New Thread 11216.0x1698]
[Thread 11216.0x1698 exited with code 1]
[Thread 11216.0x2170 exited with code 1]
[New Thread 11216.0xfd8]
[New Thread 11216.0x356c]
[Thread 11216.0xfd8 exited with code 1]
[Thread 11216.0x356c exited with code 1]
[New Thread 11216.0x520]
   - C380004 Discriminant-dependent entry families for protected types.
[Thread 11216.0x520 exited with code 1]

Program received signal SIGSEGV, Segmentation fault.
___chkstk_ms () at
/cygdrive/c/Users/didier/git/gcc/libgcc/config/i386/cygwin.S:146
146             orq     $0x0, (%rcx)            /* probe there */
(gdb) info registers
rax            0x283b0  164784
rbx            0x880e80 8916608
rcx            0xffe032d0       4292883152
rdx            0x0      0
rsi            0xffffc2d0       4294951632
rdi            0xffffcab0       4294953648
rbp            0xffffc350       0xffffc350
rsp            0xffffc2b8       0xffffc2b8
r8             0x0      0
r9             0x0      0
r10            0xffffcab0       4294953648
r11            0x10042d9c9      4299348425
r12            0x100441768      4299429736
r13            0x100441958      4299430232
r14            0x1004416a0      4299429536
r15            0x100441720      4299429664
rip            0x10043b0b6      0x10043b0b6 <___chkstk_ms+22>
eflags         0x10202  [ IF RF ]
cs             0x33     51
ss             0x2b     43
ds             0x2b     43
es             0x2b     43
fs             0x53     83
gs             0x2b     43
(gdb) up
#1  0x000000010040dfb2 in c380004.chk () at c380004.adb:132
132                     X : Arr;