[Bug fortran/119136] Printing result of function that prints itself hangs

[jvdelisle at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119136

--- Comment #10 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> ---
I looking around in libgfortran/io I found a file called lock.c.

At the top of this file is a comment:

/* Thread/recursion locking ...

The content of the file is very short and it contains no obvious locking
mechanism though I can see how we might do this.  The file was created in 2004.
Thus, "we" have been aware of this requirement since the creation of the
universe.

I think this will be a good place to put a check. We do have to be careful of
the asynchronous I/O implemented elsewhere. I will be thinking on this.