Re: GNUstep and valgrind

[Riccardo Mottola]

Hi amon,

amon wrote:
> Thanks for all the discussion. Very useful. A few new folks
> got involved, so I'll re-iterate that the environment is a
> circa 2012 Ubuntu LTS with gcc tool chain on an board intended
> for embedded systems which is difficult to upgrade to new
> releases and quite brick-able. I may change at some point in
> the future when that is feasible but for the moment clang is
> out. I went through hell with some issues of installing clang
> into some versions of Mint and Ubuntu... there was a serious
> compiler issue that I spent a month figuring out and built up
> a matrix of OS's. I got it down to a simple test program that
> crashed if the system was faulty. Greg can probably tell you
> about it. He may remember answering questions as the horror
> story developed.
>
> That's one reason why I'm sticking to gcc until our hardware
> vendor upgrades to an LTS that is significantly past the
> period in which the issue sometimes happened.

Rest assured that you can be perfectly fine with GCC. Enjoy "old style" 
objective-c and it works.. I never felt the need for Obj-C 2 of which I 
see an ugly syntax, neither I want ARC or GC, remembering the dark ages 
when I was a Java programmer!
GCC in certain release is a proven compiler, but in other releases it is 
a mess. For every platform you have the best mix&match.

Of course, Obj-C in GCC would need some care.. sometimes it spits out 
warnings that are nonsense.. and speed got worse with modern GCCs (but 
clang is perhaps worse...)

> So its a given that for now, I am constrained to gcc.

GNUstep and all the software I work on works on GCC, there are no limits 
what you can do with it! It is Turing-complete!
Of course, if you do old-style memory-handling, you need some extra 
care, but it will work just fine.

I most probably run GNUstep on systems with less memory than you do.

Generally, GNUstep could need some sort of "slimming down options" but 
with tests I did with Richard, it does not leak. Or better: there are 
apps and things that leaks, but it is their fault, gnustep-core is quite 
decent.

> Also, this is not a new program, so I am trying to develop
> the least possible change set to fix the storage management
> issues... it's about 10,000 lines of operationally tested
> code, some of which pre-dates using GNUstep entirely.
>
> It makes life interesting and adds lots of constraints.

Check that they are really "issues". I did check several daemons and 
apps and with a careful use of ref-count and ARPs, they are not really 
leaking, although there is some memory waste.
We all like to be memory-savvy, but leaks are a different things.

> So again, thank you for the discussion. It has a lot of ideas
> percolating in my head as I face the new day of coding. :-)

Of course... look at what I am compiling GNUstep on right now:

NetBSD 7.1 (GENERIC.201703111743Z)
HP9000/715/50 (Scorpio)
real mem = 81920 KB (73728 reserved for PROM, 69768 KB used by NetBSD)
avail mem = 68512 KB
kern.module.path=/stand/hppa/7.1/modules
timecounter: Timecounters tick every 10.000 msec
mainbus0 (root) [flex fff80000]
pdc0 at mainbus0
power0 at mainbus0: not available
cpu0 at mainbus0 hpa 0xfffbe000 path 8 irq 31: PA7100 (T-Bird) rev 0
cpu0: PCXT, PA-RISC 1.1b, lev 1, cat A, 50 MHz clk
cpu0: shadows, 64K/64K D/I caches, 120 shared TLB, 16 shared BTLB
cpu0: PCXT (Rolex - CMOS-26B) floating point, rev 1
mem0 at mainbus0 hpa 0xfffbf000 path 9: viper rev 0, ctrl 
0x19a10000<lpmc_en> size 80MB

the processor with no stack.. finest for searching memory errors!

Or this:
Mar 20 23:13:34 shadowfax unix: Copyright (c) 1983-2002, Sun 
Microsystems, Inc.
Mar 20 23:13:34 shadowfax unix: Ethernet address = 8:0:20:93:f3:23
Mar 20 23:13:34 shadowfax unix: mem = 589824K (0x24000000)
Mar 20 23:13:34 shadowfax unix: avail mem = 575381504
Mar 20 23:13:34 shadowfax unix: root nexus = Sun Ultra 1 UPA/SBus 
(UltraSPARC 167MHz)

the perfect machine to check for invalid struct issues, memory 
alignment, pointere dereferencing...

PA-RISC and SPARC are among my favourite machines and they uncover so 
many errors that go undiscovered on intel...

Riccardo