Odd hang of cc1.exe *now further isolated, potential console issues* cpp/gcc

[Shaddy Baddah]

Hi Eliot,

On 28/4/20 10:46 pm, Eliot Moss wrote:
> Could it be a cygwin fork problem?  Definitely possible
> in a 32-bit environment.  I had to rebase all the time.
> Now that I'm mostly in the 64-bit environment it's not
> such an issue.

I suspected so and did trigger a rebaseall... it hasn't helped.
As mysterious as this problem is, I can't rule out fork issues, but I
have new information that suggests it might be something odd with
console/pty I/O???

So, if I run cc1 from bash, under a command prompt window, it will
will seemingly hang. However if I enter ctrl-d, the command resumes
and seems to run (I can't say if correct or not).

Here's what I mean:

| $ /usr/lib/gcc/x86_64-pc-cygwin/9.3.0/cc1.exe -E -quiet -v -idirafter 
/usr/lib/gcc/x86_64-pc-cygwin/9.3.0/../../../../lib/../include/w32api 
-idirafter 
/usr/lib/gcc/x86_64-pc-cygwin/9.3.0/../../../../x86_64-pc-cygwin/lib/../lib/../../include/w32api 
hello.c -mtune=generic -march=x86-64
<nothing happens>
<enter ctrl-d>
|
| Analyzing compilation unit
| Performing interprocedural optimizations
|  <*free_lang_data> <visibility> <build_ssa_passes> <opt_local_passes> 
<remove_symbols> <targetclone> <free-fnsummary> <emutls>Streaming LTO
|  <whole-program> <fnsummary> <inline> <free-fnsummary> 
<single-use>Assembling functions:
|  <materialize-all-clones> <simdclone>
| Time variable                                   usr           sys 
     wall               GGC
|  phase setup                        :   0.01 (100%)   0.00 (  0%) 
0.01 ( 40%)    1224 kB ( 90%)
|  phase opt and generate             :   0.00 (  0%)   0.00 (  0%) 
0.01 ( 28%)       2 kB (  0%)
|  TOTAL                              :   0.01          0.00 
0.03           1357 kB
|
| $

If I try this in mintty, the ctrl-d isn't accepted, and the hard hang
continues. ctrl-c doesn't work, and I have to resort to killing
processes in taskmgr (haven't tried just using Cygwin kill. Can if it
makes a difference).

So, it seems like even though cc1 is probably not reading the console,
Windows things it needs events from that source for some reason??? It's
all a bit above my pay grade at the moment.

Also, for completeness, I went back to Cygwin DLL 3.0.6-1, and the
problem persisted. Mind you, until recent modifications to the desktop
(Windows updates, and whatever other agents pushed by corporate IT)
gcc/cc1 was working with 3.1 series DLLs... go figure :-(

Any ideas?

-- 
Regards,
Shaddy