BBB/AM335x: isspace() results in data abort exception in strtol() in strtol.c and strtoul() in strtoul.c

[Jarielle Catbagan]

Ed,

I was doing some further investigation last night and I found the same
results as well in that for some reason the table that __ctype_ptr__
is suppose to point to is not included in the build, and hence not
updated accordingly.

I had a look at the standard-defined header file <ctype.h> that was
included when I installed "arm-none-eabi-gcc" and found the
declaration of __ctype_ptr__.

>From <ctype.h> it is:

extern __IMPORT char *__ctype_ptr__;


If I am interpreting this correctly, implementations that include
<ctype.h> rely on __ctype_ptr__ to be defined else where.  The
question is where?  Could it perhaps be defined in the chunk of code
along with the ctype-ish table, but is not included by gcc which is
why the link fails without the declartion of the __ctype_ptr__.

To me, it makes sense that the __ctype_ptr__ should be updated
appropriately during the build process right after the ctype-ish table
is integrated.  This leads me to the question as to what could be
missing during the link process?  I'll definitely be looking into this
more.

I was thinking a solution to this, which would probably not be
practical and elegant and possibly only a temporary one if ever, is to
define the ctype-ish table and just update __ctype_ptr__ to point to
that.  That's probably only a last case scenario.  It would make sense
that this table should be pulled into the build automatically, but
it's not.  I'll be looking more into this.

I agree that we should transition now to the RTEMS tools that way
we'll be able to focus solely on any issues that can arise when using
the RTEMS tools rather than focusing on the issues with
arm-none-eabi-gcc/etc. which probably won't matter once we transition
over.

On Tue, Jun 23, 2015 at 4:00 AM, Ed Sutter <edsutterjr at gmail.com> wrote:
> On 6/22/2015 9:54 AM, Ed Sutter wrote:
>>
>> isspace() seems to be pulled in just fine from
>> /usr/arm-none-eabi/include, because removing <ctype.h> from strtol.c
>> results in an undefined reference to isspace().
>
> Jarielle,
> The ctype.h file usually just includes the macros that depend on
> some ctype-ish array.  So, you're right that the header file is
> correctly pulling in the macros; but that's not the end of it.
> I think the problem (aside from the fact that we need to get on
> the RTEMS compiler) is that this array (apparently called or
> pointed to by "__ctype_ptr__") does not exist in the build;
> hence my incorrect attempt to cure the problem by declaring
> __ctype_ptr___ in docmd.c
>
> So, I suggest getting on the RTEMS compiler, removing those __ctype_ptr__
> declarations at the top of docmd.c and building again.  Figure out why
> the ctype array is not being pulled in by a basic library and my hunch is
> you'll be good-to-go with this problem.
> Ed
>
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