[Bug sanitizer/80386] UBSAN: false positive - constant folding and reassosiation before instrumentation

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80386

--- Comment #3 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Yea, the fold call there is puzzling.  Even a change in r67189 (old one!) had:

-  /* Don't fold a COMPONENT_EXPR: if the operand was a CONSTRUCTOR (the
-     only time it will fold), it can cause problems with PLACEHOLDER_EXPRs
-     in Ada.  Moreover, it isn't at all clear why we fold here at all.  */
-  if (TREE_CODE (t) != COMPONENT_REF)
-    t = fold (t);

Does anything break if we get rid of the fold call?