Segfaults in error traces caused by modules

[Alan Bateman]

On 09/11/2016 11:42, Andrew Haley wrote:

> I'm seeing repeated segfaults in error traces.  These seem to be caused by
>
> void frame::print_on_error(outputStream* st, char* buf, int buflen, bool verbose) const {
>    if (_cb != NULL) {
>      if (Interpreter::contains(pc())) {
>        Method* m = this->interpreter_frame_method();
>        if (m != NULL) {
>          m->name_and_sig_as_C_string(buf, buflen);
>          st->print("j  %s", buf);
>          st->print("+%d", this->interpreter_frame_bci());
>          ModuleEntry* module = m->method_holder()->module();
>          if (module->is_named()) {
>            module->name()->as_C_string(buf, buflen);
>            st->print(" %s", buf);
>            module->version()->as_C_string(buf, buflen);
>
> where module->version() returns NULL.
>
>
The version is optional and so modules may be defined to the VM with a 
version string of NULL. It may be that this code has only been tested 
with images builds, where the platform modules have version ("9" or 
"9-internal" ...). However with an exploded build then the platform 
modules don't have a version string and I assume this is where you hit this.

-Alan