[MLton] Question on Investigating Segfaults in Compiler
Thu, 8 Jul 2004 09:23:51 -0700 (PDT)
I decided to take a stab at generating a MLton
executable free of the Cygwin compatibility layer. I
know Johnny (Anoq) has done this before in the past,
though via a bit of a tortuous route (see
http://www.hardcoreprocessing.com for details).
For better or worse, what I did was as follows:
1. Modified the upgrade-basis script to include a new
2. Modified the 'platform' script to understand the
3. Modified a host of Runtime sources to do
Win32-specific stuff where possible. Luckily the GC
has already been modified in this way.
4. I rebuilt MLton under Cygwin with my new basis
(that included the Mingwin terms), then copied this
over to my MINGW environment and verified it could
build test programs.
5. I then did a "make all-no-docs" and corrected a
bunch of typo's I had made in the runtime modules, and
watched as everything linked properly.
6. The make process then segfaults while trying to
build the basis library.
(gdb) run @MLton --
@MLton -- /c/fulgham/projects/mlton/build/lib/world
Program received signal SIGSEGV, Segmentation fault.
0x00558244 in Chunk199 () at mlton.199.c:5997
5997 Raise ();
#0 0x00558244 in Chunk199 () at mlton.199.c:5997
#1 0x02983370 in ?? ()
(gdb) Cannot access memory at address 0x14e
5992 Push (152);
5993 FarJump (7, 48242);
5996 GPNR(0) = G(Pointer, 4443);
5997 Raise ();
5999 case 6353:
6000 Push (-156);
6001 S(Pointer, 152) = S(Pointer, 156);
I suspect that some aspect of the runtime changes I
made is causing this, but I'm not sure how to map the
generated C code to the offending piece of the runtime
Any recommendations on how to backtrack from here?