[Bug tree-optimization/41905] [4.5 Regression] ICE with __attribute__((noreturn))

[jason at gcc dot gnu dot org]

------- Comment #2 from jason at gcc dot gnu dot org  2009-11-09 17:18 -------
This is happening because in C++ mode the body of bar looks like

D.1729 = foo ();
D.1728 = D.1729;

whereas in the C front end it looks like

D.1986 = foo ();

and so gimple_seq_may_fallthru says that the body can fall through in the first
case, even though the first statement cannot fall through.

This difference seems to be because the INIT_EXPR within the RETURN_EXPR is
initializing a temporary in C++ vs. the RESULT_DECL in C.

I'm not sure where we ought to be pruning the dead assignment to D.1728, but it
doesn't seem like the front end's job.


-- 

jason at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jason at gcc dot gnu dot org
          Component|c++                         |tree-optimization


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41905