Select location of divesite in new map widget

[Dirk Hohndel]

> On Oct 3, 2017, at 11:02 AM, Lubomir I. Ivanov <neolit123 at gmail.com> wrote:
>>> yey, a compiler bug (stack corruption) in:
>>> gcc version 5.3.0 (i686-posix-dwarf-rev0, Built by MinGW-W64 project)
>>> 
>>> in divelistview.cpp, for this:
>>> for (int col = DiveTripModel::NR; col < DiveTripModel::COLUMNS; ++col) {
>>> 
>>> instead of incrementing col up to 16, it goes up to 2689.
>> 
>> Sweet. If you look at the preprocessor output, is it the DiveTripModel::COLUMNS
>> that is incorrectly expanded, or is it really the code generation?
>> 
>> And given that Gaetan sees this on Arch... different compiler, right?
>> 
>> WEIRD
>> 
> 
> apparently, the stack gets corrupted by out-of-bounds access...how?
> i'm not sure, but i won't disassemble this as there is an easy fix and
> we are doing something wrong.
> 
> divelistview.cpp has this:
> static int defaultWidth[] =    {  70, 140, 90,  50,  50,  50,  50,
> 70,  50,  50,  70,  50,  50,  5, 500};
> 
> the loop uses the 'col' iterator which is clamped up to
> DiveTripModel::COLUMNS, but DiveTripModel::COLUMNS is larger than the
> N of elements in defaultWidth.
> 
> so the first out-of-bound access to:
> defaultWidth[col]
> 
> modifies the loop's limit to something like 2689 and it proceeds with
> the out-of-bound access until a SIGSEGV.

That makes more sense.
We need to figure out why we overwrite the stack! Can you set a memory
breakpoint to see where this happens?

> fixes:
> 1) add another element to defaultWidth[] for 'country' and iterate col
> up to the size of defaultWIdth[].

can you submit a patch?

> 2) move defaultWidth as a method in DiveTripModel, for safety

What do you mean by that?

/D