Fwd: Intrumenting memory accesses and internal segfault

[hugo brunie <hbrunie0@xxxxxxxxx>]

Hi,
Inspired from thread_sanityzer GCC pass I am trying to instrument every
memory access of a chosen function.

Through the gate of my pass (GCC plugin 6.1), I only instrument function
which name is present in a text file.
Then I changed a little bit of thread_sanytizer pass to instrument every
memory access inside these functions.

My problem happens on C++ code as simple as :

int main(int argc, char * argv[])
{
    Domain dom;
    int b = dom.relt();
    int a = dom.elt();
    return 0;
}

in domain.hpp there is : the domain class with relt returning a reference
and elt returning a const NO reference.

The SSA code generated is :

Location: File (simple_main.cpp) Line (8)
  <bb 2>:
  DomAin::DomAin (&dom);
  <bb 3>:
  b_4 = DomAin::elt (&dom);
  # DEBUG b => b_4
  _6 = DomAin::relt (&dom);
  *correspondance_instrument_load_store* (11, _6, &"simple_main.cpp"[0]);
  a_7 = *_6;
  # DEBUG a => a_7
  _8 = 0;
  dom ={v} {CLOBBER};
  return _8;
<L2>:
  dom ={v} {CLOBBER};
  resx 1

BUT if I just left either

int b = dom.relt();
OR
int a = dom.elt();
alone in the main, there is no segfault.

Error trace :
0xac0eff crash_signal
        ../../gcc/toplev.c:333
0x93374e inline_edge_summary
        ../../gcc/ipa-inline.h:281
0x93374e estimate_function_body_sizes
        ../../gcc/ipa-inline-analysis.c:2648
0x937066 compute_inline_parameters(cgraph_node*, bool)
        ../../gcc/ipa-inline-analysis.c:2953
0xb5fe9a convert_callers_for_node
        ../../gcc/tree-sra.c:5112
0xb69a9e cgraph_node::call_for_symbol_and_aliases(bool (*)(cgraph_node*,
void*), void*, bool)
        ../../gcc/cgraph.h:3071
0xb69a9e convert_callers
        ../../gcc/tree-sra.c:5127
0xb69a9e modify_function
        ../../gcc/tree-sra.c:5183
0xb69a9e ipa_early_sra
        ../../gcc/tree-sra.c:5411
0xb69a9e execute
        ../../gcc/tree-sra.c:5458

Thank you for your help,

 - Hugo