[Bug sanitizer/91439] Wrong debug information with -fsanitize=address

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91439

--- Comment #3 from Martin Liška <marxin at gcc dot gnu.org> ---
We rewrite:

main (int argc, char * * argv)
{
  int D.2275;
  int _3;

  <bb 2> :
  f (&argc);

into:

main (int argc, char * * argv)
{
  int argc;
  int D.2275;
  int _3;

  <bb 4> :
  argc = argc_4(D);

  <bb 2> :
  f (&argc);

when I make a step in the function, I get proper value:
4           f(&argc);
(gdb) p argc
$2 = 1

We build a GIMPLE assignment:
g = gimple_build_assign (var, tmp);

@Jakub: What should I do to say that the VAR_DECL has the same value as
PARM_DECL at the very beginning of the function?