Hi Brad,
About the GCC bug that sometimes GCC could take gigabytes of RAM (20-75GB) for certain Gambit files,
I re-read your previous article at http://webmail.iro.umontreal.ca/pipermail/gambit-list/2009-February/003159.h... .
(Btw the mentioning of an addition to http://dynamo.iro.umontreal.ca/wiki/index.php/Configure_script_options , I don't know if I see that addition there, you could doublecheck.)
You mention there that the problem GCC versions are 4.2.* and 4.3.* only, and that "-fno-move-loop-invariants" fixes it.
(I recall that you also reported the issue to the GCC development team and that in response they implemented a "max loops" check internally that fixed it on.. later GCC version, something like this.)
I just wanted to check with you now, that the above was all there has been to GCC's skyrocketing-RAM-consumption issue. So, if I just add CFLAGS="-fno-move-loop-invariants" to my ordinary "./configure --enable-single-host" etc. , no GCC/G++ version will skyrocket?
Are there any more gotchas to GCC use for various versions, except for that "-O2" produces broken code in some particular version?
Thanks!
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On 02/20/2016 04:49 PM, Adam wrote:
Hi Brad,
About the GCC bug that sometimes GCC could take gigabytes of RAM (20-75GB) for certain Gambit files,
...
Are there any more gotchas to GCC use for various versions, except for that "-O2" produces broken code in some particular version?
Well, I don't know, I don't follow all gcc development, it seems impossible to answer this question the way it's stated.
If you find a problem I'll look into it.
Brad
2016-02-23 4:23 GMT+07:00 Bradley Lucier lucier@math.purdue.edu:
On 02/20/2016 04:49 PM, Adam wrote:
Hi Brad,
About the GCC bug that sometimes GCC could take gigabytes of RAM (20-75GB) for certain Gambit files,
...
Are there any more gotchas to GCC use for various versions, except for that "-O2" produces broken code in some particular version?
Well, I don't know, I don't follow all gcc development, it seems impossible to answer this question the way it's stated.
If you find a problem I'll look into it.
Brad
Ok I'll narrow down my question:
To make Gambit work well (with --enable-single-host) on 4.2.* and 4.3.*, is "-fno-move-loop-invariants" a complete solution?
(The prob AFAIK was that it'd skyrocket to 20-75GB RAM consumption - and "-fno-move-loop-invariants" would bring it down to 1-2GB instead?)
On 02/22/2016 04:31 PM, Adam wrote:
2016-02-23 4:23 GMT+07:00 Bradley Lucier <lucier@math.purdue.edu mailto:lucier@math.purdue.edu>:
On 02/20/2016 04:49 PM, Adam wrote: Hi Brad, About the GCC bug that sometimes GCC could take gigabytes of RAM (20-75GB) for certain Gambit files, ... Are there any more gotchas to GCC use for various versions, except for that "-O2" produces broken code in some particular version? Well, I don't know, I don't follow all gcc development, it seems impossible to answer this question the way it's stated. If you find a problem I'll look into it. Brad
Ok I'll narrow down my question:
To make Gambit work well (with --enable-single-host) on 4.2.* and 4.3.*, is "-fno-move-loop-invariants" a complete solution?
(The prob AFAIK was that it'd skyrocket to 20-75GB RAM consumption - and "-fno-move-loop-invariants" would bring it down to 1-2GB instead?)
Yes, I think so.
But why would one consider using 4.2.* and 4.3.* when much newer compilers are available.
Brad