Re: Debugger options: difference output between linux and windows
On Fri, 15 May 2020, Massimo Sala wrote:
> * linux: -DLUA_USE_LINUX -g -b
> lua -v
> bcheck.c __bound_ptr_add: 0x7fffffffe66f is outside of the region
> bcheck.c bound_error: invalid pointer
> /opt/packages/tcc.sh: line 49: 19914 Segmentation fault ./lua -v
> From the output I cannot understand if this instrumentation is working and
> there is a problem in Lua, or there is a problem in the tcc instrumentation
> I read at https://bellard.org/tcc/tcc-doc.html "Note: -b is only
> available on i386"
> Does it mean cannot work on intel, 64 bits cpu ?
Nope, that's outdated docu, -b is supposed to work on x86-64. But I fear
you'll have to debug this a bit on your own. Current mob branch should
actually be a bit more verbose in telling where the invalid access is
happening, so it seems you're using an older version; please update to
In the worst case you can run the whole thing in a debugger and set a
breakpoint on bound_error or tcc_backtrace. In recent mob branch you can
also set the environment variable TCC_BOUNDS_NEVER_FATAL to 1, in which
case the error is only logged but the program keeps running (and possibly
accessing the invalid pointer, which might turn out to be harmless).