Re: gcc hangs even on simple compile tasks

On 3/10/2026 9:08 AM, Brian Inglis via Cygwin wrote:
> On 2026-03-06 17:29, Annihilannic via Cygwin wrote:
>> On 07/03/2026 09:37, Dick Pierce via Cygwin wrote:
>>> Starting the end of last week, gcc has started behaving badly. Whether I invoke
>>> it from a makefile or directly from bash, almost ALL of the timer, it hangs
>>> forever, and Task Manager shows cc1 as "running", but consuming no CPU as
>>> far as I can tell. If I kill it through task manager, the prompt returns
>>> in bash (or make dies with an "interrupted" error.
> 
>>> But I'm stumped.
> 
>> Smells like a hardware problem to me - I'd suggest testing it thoroughly with 
>> memtest86 or similar.
>>
>> Also run it through `strace -f gcc -o hello.exe hello.c` a few times and see 
>> if it's sticking in the same spot every time (which would indicate software)?
> 
> Never blame hardware until you have eliminated the likelihood of BLODA (Big List 
> Of Dodgy Apps <https://www.cygwin.com/acronyms/#BLODA>: FAQ 4.44.
> 

I went so far as wiping the machine completely of cygwin, pulled all
references to cygwin out of the registry[1], and reinstalled cygwin
from scratch: no change in behavior at all.

After multiple dead end rabbit holes (redundant?), the problem was none
of what anyone thought it was: it was MUCH simpler.

Out of desperation and on a hunch, I did a search of the machine for all 
instances cygwin1.dll on the machine. I had 6 copies spread all over the
place. Crucially, there was one in c:/windows/system. Got rid of that one,
all of a sudden, gcc started working just fine. And since /windows/system
has near the head of PATH, it was the one that got done first. Did a compare
of that one to the one in /cygwin64/bin and, yes, it was different.

So I then did a purge of my system of every instance of cygwin1.dll across
the system I could find EXCEPT the one that came with the latest cygwin
installation. How the crucial one ended up in /windows/system, I have
NO idea. But often, looking at the simplest and, perhaps, dumbest cause
of a problem is best done first.

FOOTNOTES
==========
[1] What does the Windows registry and Florida have in common? it's a place
     where things go to die.