[MLton] compiled binary freezes on solaris during LargeReal.fromLargeInt()

[Matthew Fluet]

On Mon, 15 Sep 2008, Nicolas Bertolotti wrote:
> When you compile and run the following program on Solaris, using a compiler based on the latest SVN sources (r6853):

I assume this is on a Sparc (as opposted to an x86 or amd64).

> val _ = print("OK1\n");
> val x = Time.toNanoseconds(Time.now());
> val _ = print("OK2\n");
> val y = LargeReal.fromLargeInt(x);
> val _ = print("OK3\n");
>
> It freezes (using all CPU resources) after printing the string < OK2 >.
>
> The same piece of code runs fine when it is built using the latest official release.
>
> Any idea?

The codepath for LargeReal.fromLargeInt is mostly in the GnuMP and gdtoa 
libraries (see 'val fromIntInf' in <src>/basis-library/real/real.sml).

I would suggest compiling the program with "-debug true" and running the 
executable under gdb; a Ctrl-C when the program spins should reveal 
whether it is in GnuMP (if you see "IntInf_toString" in the backtrace) or 
in gdtoa (if you see "Real64_strto" in the backtrace).

I would also suggest building MLton 20070826 from source on this machine 
and compiling the program.  That would reveal whether there is something 
specific about this machine (version of gcc, etc.) that triggers the 
behavior or there is some change to the compiler from 20070826 to HEAD 
that triggers the behavior.