<verbatim>
> Hmmm, it seems the lldb debugger cannot be trusted with -01
</verbatim>

<p>
It can be trusted, but debugging optimized code is uncomfortable, because the optimization is reorganizing the code a bit, and some variables will be replaced by registers, or simply removed.

<p>
If I look onto the results then I guess that the font initialization of the Mac code has any severe problem, and is probably destroying the hash table (sharedTextPtr->tagTable). So I think that the font initialization while performing

<verbatim>
   tagPtr->optionTable = Tk_CreateOptionTable(textPtr->interp, tagOptionSpecs);
</verbatim>

<p>
needs investigation. Later, wen the lines tkTextTag.c:1924-1931 will be executed, one of the functions Tcl_CreateHashEntry(), or more likely Tcl_GetHashKey(), seems to corrupt the stack, as a side-effect.