[Bug sanitizer/113012] [13/14 regression] ICE when building xorg-server with -fsanitize=undefined

[rguenth at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113012

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
Btw, we're trying to gimplify

_29 = _35;, 0 = _36;

built here:

#0  bundle_sizes (name=<integer_cst 0x7ffff6a0bf78>, 
    expr=<ssa_name 0x7ffff6824ab0 36>)
    at /home/rguenther/src/trunk/gcc/tree-object-size.cc:242
#1  0x0000000001804ee4 in object_sizes_set (osi=0x7fffffffd7c0, varno=12, 
    val=<ssa_name 0x7ffff6824ab0 36>, wholeval=<ssa_name 0x7ffff6824a68 35>)
    at /home/rguenther/src/trunk/gcc/tree-object-size.cc:277
#2  0x0000000001805203 in object_sizes_set_temp (osi=0x7fffffffd7c0, varno=12)
    at /home/rguenther/src/trunk/gcc/tree-object-size.cc:333
#3  0x0000000001809ce5 in collect_object_sizes_for (osi=0x7fffffffd7c0, 
    var=<ssa_name 0x7ffff6824240 12>)
    at /home/rguenther/src/trunk/gcc/tree-object-size.cc:1718
#4  0x0000000001809236 in dynamic_object_size (osi=0x7fffffffd7c0, 
    var=<ssa_name 0x7ffff6824240 12>, size=0x7fffffffd690, 
    wholesize=0x7fffffffd688)
    at /home/rguenther/src/trunk/gcc/tree-object-size.cc:1483
#5  0x0000000001809b09 in phi_dynamic_object_size (osi=0x7fffffffd7c0, 
    var=<ssa_name 0x7ffff6824048 5>)
    at /home/rguenther/src/trunk/gcc/tree-object-size.cc:1642

that's

  tree oldval = osize.size;

being INTEGER_CST zero which doesn't exactly look "wrong"?  Or does this
mean there's conflicting sizes?

I believe there's something wrong with the processing of dynamic object sizes.